Damages cited in the complaint total about Bt64 million but it is believed that there are more victims.

Pol Colonel Somchai Phosuwan, a deputy investigator of Economic Crime Suppression Division, said Dr Nitcha Rutthapichairak, 30, an Air Force officer who works at a government hospital, had filed a complaint against a fellow doctor whose name was not revealed on Sunday.

In the complaint, the plaintiffs said the unnamed doctor had cheated them by encouraging them to invest in a tour company, claiming money was needed for the advance booking of rooms for Chinese tourists. The investors were allegedly told that the tourists were arriving in a big group and that the tour company needed initial capital to reserve the rooms.

The complaint states that doctor in question promised to pay investors 6 to 18percent returns per month.

However, the company failed to pay the promised returns, and when the plaintiffs queried the unnamed doctor about the issue, she did not answer and went missing from her house and office, the complaint states, concluding there was no other option other than going to the police.

Nitcha said she and the other 12 plaintiffs had filed the complaint on behalf of 38 victims.

Reportedly the doctors were friends in high school, but had lost touch while at university and after graduation, only to reestablish contact again on Facebook.

Somchai said he was gathering information from the plaintiffs, which should be completed by Friday. “If we conclude that there is fraud, we will summon the doctor for questioning,” he said.

Nitcha told reporters on Sunday that the tour company belonged to the boyfriend of the unnamed doctor and many friends in her professional circle, most of whom are doctors, were eager to invest in the firm because of its apparent profitability.

“The investments ranged from Bt80,000 to Bt12 million. They decided to join the business partly because that doctor works at a wellknown government hospital,” she told reporters on Sunday.

She said the business was not a Ponzi scheme because investors did not have to recruit other members and their returns did not depend on the total number of investors.

Nitcha said that she had invested Bt500,000 in the scheme last August by depositing the money into the unnamed doctor’s bank account. From August until February, she received profits of Bt300,000, which she kept in the bank, raising her total investment to Bt1 million. However, she said, in March she stopped receiving returns and her Facebook friend disappeared.