An investigation is being launched into the riot at Buri Ram prison on Sunday, during which 11 inmates escaped, Corrections Department deputy director-general Pol Lt Col Prawut Wongsrinil said on Monday.
He said the riot was started by about 100 inmates and began about 11.45am on Sunday. The situation was brought under control in the night by police, but not before many buildings and structures inside the prison, but not the hospital, had been burned down.
The 2,106 prison inmates had since been transferred among 18 other nearby prisons in the Northeast, he said.
Eleven inmates escaped during the riot, after breaking through a wall in the visiting room for relatives. Ten of them were recaptured, some right outside the prison.
The sole escapee still at large was Tanyapong Sinpoon, 26, serving time for drugs in possession with intent to sell, unlicensed possession of a firearm and resisting arrest.
Pol Lt Col Prawut said the inmates who took part in the riot would be questioned. How long this took would depend on how cooperative they were.
Pol Col Naras Savestanan, the Corrections Department chief, was setting up an investigation panel to establish the cause of the riot, he said.
Pol Lt Col Prawut said a rumour that spread in the prison, that an inmate was infected with Covid-19, was not true. This might have been suggested by a suspected mastermind, a convict serving a long sentence.
"The inmates and their relatives have told that with the strict screening measures in place, there is no chance for the virus to spread in the prison.
"But prison officials may need to do more homework on this matter," he added.