Most of the first batch in what is expected to be waves of thousands of illegal labourers returning from hard-hit South Korea were cleared in airport screenings.

Nineteen of the 158 arriving at three airports starting on Tuesday were found to have fever and detained for follow-up physical examinations, he said, citing an Immigration Department report.

They too were subsequently declared virus-free.

“The rest were allowed to go, but must stay into self-quarantine at home for 14 days,” he added. “Staff from Department of Disease Control will monitor their condition closely on a daily basis.”

The ministry has been unable to confirm the number of labourers returning and has asked South Korea to send a list of names urgently.

The number could be as many as 100,000, it’s been estimated.