His Majesty the King and Her Royal Highness Princess Bajrakitiyabha have sent a mobile Covid-19 testing vehicle to Narathiwat prison, where 126 inmates and warders were found infected with the virus, Justice Minister Somsak Thepsuthin said on Monday.
The on-site biosafety rapid test vehicle was well equipped to collect samples for coronavirus testing.
Mr Somsak said a total of 126 people were found to have been infected in the prison cluster.
Of these, 95 inmates and 25 prison officials tested positive for the virus at Narathiwat prison. Eighty-eight were being treated in zone 2, three in zone 6 and one in the women's zone inside the prison, and the other three at Narathiwat hospital.
The other six, five inmates and one official, were found infected while taking part in an anti-drugs seminar in Surat Thani. They were being treated at Surat Thani hospital.
Mr Somsak said a field hospital would be set up in zone 2 of the prison, staffed by public health officials and medical staff from Narathiwat hospital and the Corrections Department. It would have room for 200 patients.
If necessary, an area in zone 6 would be turned into a field hospital, so up to 600 patients could be treated in total.
Patients in a serious condition would be sent to nearby hospitals.
About 200 inmates with chronic illnesses would be the first group to be tested for Covid-19, he said.
Mr Somsak said the seminar in Surat Thani was also attended by 57 inmates from Thung Khen temporary prison in Kanchanadit district and 63 officials from the Probation Department.
All of them would be isolated for seven days for observation.
Since Thung Khen prison was not surrounded by a fence or wall, the inmates would be fitted with electronic tags by the Probation Department to prevent them fleeing and spreading the disease.
He believed the Covid-19 virus spread from Narathiwat prison, not from Surat Thani.
It might have been introduced to the prison by an inmate who came from a neighbouring country or by an official who regularly went in and out.
This was still being investigated, Mr Somsak said.