Thailand’s Corrections Department has offered a 100,000-baht reward for anyone who provides information leading to the arrest of a convict who escaped from a hospital in the southern province of Nakhon Si Thammarat early Sunday morning.

The fugitive, 37-year-old Chavalit Thongduang, was sentenced to 21 years and three months in prison on robbery and firearms charges. Last Friday, he was taken from the prison to Maharaj Nakhon Si Thammarat Hospital for dental treatment. He passed out and was admitted to the hospital, but he slipped out of the hospital.

Aryut Sintoppant, the department’s director-general, said that they have sought help from the local police and the military in tracking the fugitive down.

He also said that an investigation has been ordered into how Chavalit managed to escape from the hospital and whether any prison officials were involved in helping him.

According to the police report, there are still several criminal cases pending against Chavalit, including illegal narcotics trafficking, money laundering and murder.