It was not clear if the decision to release the 13 religious teachers, or ustads, came after a group of Muslim lawyers had petitioned a Yala court this week to seek their release on the ground of insufficient evidence.

The remaining ustad was identified as Chaihidan Boonyang, a resident of Satun province who teaches part time at the Thammawitthaya School in Yala.

He is being question for further questioning, said a lawyer familiar with the issue but refused to named.

He said lawyers in the region plans to step up their quiet campaign for the release of the last remaining ustads.

A total of 19 teachers and their boat operator were detained under Emergency Law two weeks ago. Police became suspicious after the teachers, all of whom taught at the Thammawitthaya School, had gathered on a small island just of the coast of Satun.

One of the 19 detained ustads said he was angry at being held for two weeks without charges but felt helpless not knowing where to turn.

"Mine was only a few days but I kept thinking of all the fellow ustads (Islamic teachers) who had been held in detention for years and in far away places," said one teacher on condition of anonymity.

"My family members come and see me everyday but what about those who are locked away and forgotten," he added.

Police has remained tightlip over the detention or their decision to release the teachers but would only cite security mandate granted to them under the Emergency Law.

Thammawitthaya School has been in an unwanted spotlight after its principle and cofounder, Spaeing Baso,  went on the run amidst a swirl of accusations that he is behind the violence that has plagued the region.

The government two years ago accused a number of its teachers of orchestrating violent attacks in the region.

More than 1,100 people have died in the region over the past two years in violent attacks and the government's heavy-handed reaction to them.

The Nation