Cleaners disinfect a restaurant in Chiang Rai, northern Thailand, today (March 5) after a worker returned from coronavirus hot-spot South Korea ate there.

The overseas worker, one of 5,000 Thais returning from South Korea where 40 have died so far, took their family to the BBQ grill restaurant on Tuesday (March 3).

But staff later learned that they had been serving someone who was at high risk of carrying the deadly COVID-19.

Restaurant owner Watcharin Noi Phut, 39, said: ''We saw on social media that the person who recently returned from Korea had eaten here. So we immediately closed the restaurant and began cleaning every surface.''

Thai Prime Minister General Prayut Chan-ocha confirmed today that illegal Thai workers from Daegu, in South Korea, must be put under quarantine for 14 days to prevent the possible spread of the disease.

While The country's Public Health Minister, Anutin Charnvirakul, said a meeting was held today to find measures to address the return of Thai workers from the rest of the country.

More than 5,000 Thai workers have been requested to travel back to Thailand following the outbreak outbreak in South Korea, which has already seen more than 6,100 infections.