In what officials described as a first-of-its-kind action, the department asked a federal court to block the companies and those who run them from carrying the fraudulent calls, alleging that they were essentially co-conspirators in a scheme to defraud those who picked up the phone.

The companies, Justice Department officials said, had been warned that the calls they were transmitting – most of which originated in India and lasted less than a second because the recipients hung up – were fraudulent, but did so anyway.

The result, officials said, was that fraudsters were able to swipe hundreds of millions of dollars by posing as government officials or employees of trusted businesses and threatening arrest or other financial harm to mostly elderly victims who responded on the phone.

“Not only are the calls an annoyance, but for elderly and vulnerable Americans, they are a serious problem,” Assistant Attorney General Jody Hunt said in a press call to announce the action.

Robocalls have surged in recent months – sparking Congress late last year to pass legislation that it hopes will cut down on the irritating interruptions and prevent fraud. Hunt said the Justice Department’s move Tuesday should “serve as a warning” to other telecommunications companies that they could be in federal authorities’ crosshairs if they do not do their part to crack down on possible fraud.

The department filed two civil cases in federal court in Brooklyn. One is against Nicholas Palumbo, 38, and Natasha Palumbo, 33, of Scottsdale, Arizona, who ran TollFreeDeals.com and sipretail.com. The other is against Jon Kahen, 45, of Great Neck, New York, who ran Global Voicecom Inc., Global Telecommunication Services Inc., KAT Telecom Inc.

None of the three people returned messages seeking comment. A federal judge in Brooklyn on Tuesday afternoon issued a temporary restraining order against Kahen and his companies.

“They are the link between scammers and consumers,” Social Security Administration Inspector General Gail Ennis said.

Authorities alleged Kahen and the Palumbos operated what are known as “voice over internet protocol carriers,” which use an Internet connection rather than a cooper phone line to carry telephone calls and pass foreign calls into the U.S.

They operated out of their homes, officials said, and needed relatively few resources. But they were still able to carry hundreds of millions of calls, officials asserted. Those who did not hang up were then met with alarming – though fake – messages, such as that their social security numbers had been compromised, their assets were being frozen or they faced imminent arrest and needed to pay large sums of money to get out of trouble, authorities said.

Neither the companies nor the people named in the civil filings were charged with any crimes, though the Justice Department asserted in court documents there were part of wire fraud schemes.

Hunt, who runs the Justice Department’s Civil Division, said the restraining orders would “stop the fraudulent conduct immediately,” but that the Justice Department was also continuing to investigate and working with authorities in India to identify those behind the calls.

But three weeks after the new coronavirus emerged as a health crisis, experts can’t yet say whether these efforts will succeed at containing an infection that now threatens at least 17 countries.

Some early signs are discouraging: Six countries, including China, have confirmed human-to-human transmission of the infection. Those include four cases in Germany connected to a single person – a worrisome sign for containment of the disease. Cases in China continue to multiply, and 5 million residents of Wuhan, where the virus originated, already have left the city, some of them surely carrying the disease.

But so far, the mortality rate is less than the rate of other severe respiratory coronaviruses: In China, where 5,974 people are infected, 131 have died through Tuesday. That is a high rate, but far less than the fatality rate of SARS and MERS. And countries like the United States that quickly began screening travelers, isolating sick people and tracing their contacts have just a handful of cases each. There have been no fatalities outside China.

Public health officials said Tuesday that they are grappling with a long list of unknowns that will determine how successful they are in limiting the toll of the widening outbreak. Those questions include how lethal the virus may be, how contagious it is, whether it is transmitted by people who are infected but show no symptoms and whether it can be largely contained in its country of origin.

“It is very striking how quickly the numbers are going up,” said Trish Perl, chief of infectious diseases and geographic medicine at the University of Texas’s Southwestern Medical Center, who has fought other respiratory virus outbreaks, including SARS and MERS – severe acute respiratory syndrome and Middle East respiratory syndrome.

“As the numbers are going up, do I think I’m concerned about the rapidity of it? Yes,” Perl said. “Do I think it may be difficult to control? Yes. But in the context of a lot of unknowns.”

Experts aren’t sure whether the rise in new cases means the virus is now widely circulating in China, whether the Chinese are doing a better job of surveillance and testing, or both.

U.S. health officials held a news conference Tuesday to reassure a wary public that, for now at least, virtually no one here is in imminent danger.

“Americans should know that this is a potentially very serious public health threat, but, at this point, Americans should not worry for their own safety,” said Secretary of Health and Human Services Alex Azar.

The new virus is not nearly as infectious as the measles virus, which can live as long as two hours in the air after an infected person coughs or sneezes, and is not comparable to the threat posed by seasonal flu, which has killed at least 8,200 people in the U.S. this season.

But Azar also acknowledged that “we don’t yet know everything we need to know about this virus.”

China agreed Tuesday to allow a World Health Organization team of experts into the country to study the coronavirus, officials of the United Nations agency said after a meeting between the organization’s director general and Chinese leader Xi Jinping.

“The two sides agreed that WHO will send international experts to visit China as soon as possible to work with Chinese counterparts on increasing understanding of the outbreak to guide global response efforts,” the statement said.

It was unclear whether the team would include experts from the U.S. Centers for Disease Control and Prevention.

But several nations continued to pursue or consider evacuating their citizens from Wuhan, including France, South Korea, Morocco, Britain, Germany, Canada, the Netherlands and Russia.

In the Philippines, immigration authorities temporarily suspended the issuance of visas for Chinese nationals upon arrival. Immigration commissioner Jaime Morente said the move was designed “to slow down the influx of group tours,” and prevent the spread of the virus.

In Hong Kong, Chief Executive Carrie Lam announced dramatic measures to stem the flow of mainland Chinese into the territory, including the closure of railways, ferries and cross-border tour buses. Flights to mainland China will be slashed by half, and the Hong Kong government will stop issuing individual travel visas to mainland Chinese, starting Thursday.

Yet for all the action taken, even the near future remains uncertain.

“There is a real possibility that this virus will not be able to be contained,” said former CDC Director Tom Frieden, who oversaw the responses to the Ebola and Zika outbreaks.

Researchers are struggling to accurately model the outbreak and predict how it might unfold, in part because the data released by Chinese authorities are incomplete. China has shared information showing when cases were reported, but not when people became ill.

Researchers also want to know more about the incubation period, currently estimated at two to 14 days, and how severe most cases are.

The virus’s fatality rate is currently just over 2 percent, if figures posted by the Chinese government are accurate. That is considerably lower than death rates from the respiratory coronaviruses that caused SARS, which killed nearly 10% of the people infected, and MERS, which kills about 35 percent.

Some experts are encouraged that none of the cases outside China seems to be severe. and that no fatalities have been recorded outside China so far.

Others cautioned that the current death rate may mean little because the most severe cases in an epidemic like this one often emerge early, when sick people present themselves to health care providers, then become fewer as public health measures are instituted and medical care strengthened.

Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, noted in an interview that the virus may have been spreading unnoticed for weeks in Wuhan before it emerged into public view.

If many people had mild symptoms, it would have been easy to miss them, and that made it harder to put control measures in place, said Jennifer Nuzzo, an epidemiologist and senior scholar at the Johns Hopkins Center for Health Security.

Experts also are unsure whether asymptomatic patients can transmit the virus. China’s health minister Ma Xiaowei alarmed officials around the world last weekend when he said his government had evidence that was occurring.

But U.S. officials have challenged that conclusion, saying they have not seen data that prove it and want the Chinese to show them. And asymptomatic patients never drive more than a small percentage of infections in epidemics like these, Fauci said.

“Even if there some asymptomatic transmission, in all the history of respiratory-borne viruses of any type, asymptomatic transmission has never been the driver of outbreaks,” he said. “The driver of outbreaks is always a symptomatic person.”

Frieden and others emphasized that even if officials cannot stop transmission, they can still reduce the number of people who get infected, as well as those who get very sick and die. One key measure – to beef up readiness and train health-care workers in hospitals to prevent the spread of illness there – is critical, for example

At the moment, U.S. officials are isolating coronavirus patients in the hospital. But that may not be practical if there are many more cases. During SARS, highly infectious patients known as “super spreaders” were responsible for the virus’ rapid spread in health-care facilities

It makes more sense to isolate someone with a mild coronavirus illness at home, said Nuzzo, the Hopkins expert. “If somebody only has a fever and runny nose, is there a need to freak out?” she said.

The action was taken against Felicia Sonmez, who covers politics for The Post, on Sunday after her tweet referencing a 2016 article about the charges against Bryant sparked an angry backlash against her, including death threats.

But after a brief investigation into the matter, The Post’s newsroom managers decided that no further action against Sonmez was warranted and that they had been out of line in publicly announcing disciplinary action against her.

“After conducting an internal review, we have determined that, while we consider Felicia’s tweets ill-timed, she was not in clear and direct violation of our social media policy,” Managing Editor Tracy Grant said in a statement. “Reporters on social media represent The Washington Post, and our policy states ‘we must be ever mindful of preserving the reputation of The Washington Post for journalistic excellence, fairness and independence.’ We consistently urge restraint, which is particularly important when there are tragic deaths. We regret having spoken publicly about a personnel matter.”

Sonmez declined to comment on Tuesday.

Sonmez sparked an angry reaction on social media after she tweeted a link to a Daily Beast article that described in detail a 19-year-old woman’s accusations against Bryant, including a violent sexual assault. The criminal case against Bryant was dropped after the woman declined to testify. Bryant later settled a civil suit with the woman, paying her an undisclosed sum. Although he admitted no guilt, he acknowledged that she considered his behavior nonconsensual.

The timing of Sonmez’s tweet appeared to shock and anger people, who attacked her via Twitter and email. After one person posted her home address online, Sonmez became so concerned about her safety that she spent Sunday night in a hotel.

Grant placed Sonmez on administrative leave on Sunday, saying in a statement that “her tweets displayed poor judgment that undermined the work of her colleagues.”

Sonmez’s suspension prompted reactions of disappointment within The Post’s newsroom. The Newspaper Guild, which represents Post newsroom employees, protested the action in a letter to Grant and Executive Editor Martin Baron.

The letter – which expressed the Guild’s “alarm” and “dismay” over the suspension of a journalist for tweeting a factual statement – attracted the signatures of 345 Post journalists as of Tuesday afternoon. It urged The Post to ensure Sonmez’s safety, to rescind any disciplinary action against her and to make a statement condemning the online abuse of its reporter.

In a statement issued Tuesday night, the Guild called Sonmez’s reinstatement “welcome” but said it was disappointed that The Post’s statement didn’t include an apology to the reporter. “We remain concerned that The Post did not take swift action to provide her with protection and support,” it said.

In an interview on Monday, Sonmez said early accounts of Bryant’s death failed to mention or played down the allegations against Bryant and that her tweet was meant to remind people of them. “The seriousness of those allegations is a valid part of his legacy and his life,” she said. “Those allegations should not be minimized in any way.”

Sonmez, herself a survivor of a sexual assault, said survivors of assault and their family members praised her for highlighting the Bryant allegations.

As the storm surrounding Sonmez intensified Sunday night, Grant instructed her to delete her original tweet about Bryant and two others defending herself against the onslaught of criticism. She complied.

In a meeting with airline executives Tuesday afternoon, White House officials said they are not banning flights yet, but said they will assess the situation daily, leaving open the possibility of a ban, people with knowledge of the meeting said.

Airlines have already canceled hundreds of flights scheduled from China’s Wuhan international airport in recent days, giving U.S. health officials a respite as they focused on the logistics of rerouting U.S.-bound travelers from the region to one of five airports for special screening.

Travelers are being funneled to airports in Atlanta, Chicago, Los Angeles, New York and San Francisco, where they are being screened for the virus. If cleared, they are allowed to continue to their final destination, officials with the U.S. Centers for Disease Control said.

The U.S. airports have been designated as enhanced screening points for travelers arriving from the region believed to be the epicenter of a new strain of coronavirus that has killed at least 132 people and sickened nearly 6,000 in China.

Infections have been confirmed in France, Germany, South Korea, Japan, Nepal, Cambodia, Singapore, Vietnam, Taiwan, Canada, Sri Lanka, and the United States.

The State Department has issued a Level 4 advisory for Wuhan, meaning “no American should travel to Wuhan while this virus continues to have impact,” Vice President Pence said Monday. Later Monday, the State Department issued a Level 3 travel advisory for all of China, urging Americans to reconsider or postpone travel to any part of the China.

Public health officials continue to say the coronavirus poses a low risk to the American public, but say the enhanced screenings at five airports are part of “proactive preparedness precautions.”

Officials familiar with Tuesday’s meeting between the airline executives and the White House said the White House made clear that any decision to ban flights will be based on the public health threat.

Health and Human Services Secretary Alex Azar on Tuesday described the outbreak as “fast moving, constantly changing,” and said senior officials are keeping a close on the outbreak to respond and keep Americans safe.

“Americans should know that this is a potentially very serious public health threat, but at this point Americans should not worry for their own safety,” he said.

The six are under quarantine at the Bamrasnaradura Infectious Diseases Institute and awaiting a third lab result.

The first patient from Heibei is a six-year-old child, detected first at an airport. Later, traces of coronavirus were found in four members of his family. The person from Chongqing went to a hospital after suspecting he had contracted the virus.

The recent Wuhan coronavirus situation in China has led to 106 deaths while some 1,500 are severely sick from the infection.

As of Tuesday (January 28), the Chinese government has closed many of its cities and controlled all entry points. They include Guangdong, Hunan, Zhejiang, Hubei (Wuhan is in this province), Tianjin, Anhui, Beijing, Shanghai, Chongqing, Jiangxi, Sichuan, Shandong, Yunnan, Guizhou, Fujian, Hebei, Guangxi, Jiangsu, Hainan, Xinjiang, Henan, Heilongjiang, Gansu, and Liaoning.

Some 3,500 are infected and 6,500 to 14,000 people are being closely monitored.

Outside China, 18 countries have reported 59 cases: 14 in Thailand (5 have recovered, 9 being monitored); 3 in Japan (2 have recovered, 1 being monitored); eight in Hong Kong; seven in Russia; five in Australia; four in Malaysia; three each in South Korea, United States, Singapore and France; two each in Taiwan, Macau and Vietnam; one each in Nepal (recovered), Canada, Cambodia, Germany, and Sri Lanka.

The World Health Organisation is in a meeting to assess the situation in China. WHO recently admitted an error in wording its report as “moderate” for global risk. According to the daily report, the risk is “very high” in China and “high” at the regional level.

The coronavirus has spread to numerous countries, and Beijing has placed Wuhan under lockdown since Thursday, January 23.

According the South China Morning Post newspaper, deaths from the virus have climbed to 106, with the Chinese government confirming there were nearly 4,500 cases so far.