Police and the army were investigating the incident in Kamphaengphet province.

"The army has sent a team to investigate the incident and has not yet ruled out the possibility that this was an act of anger from people who lost power," said Col Banyong Sirasunthorn, a spokesman for the Third Army region.

Banyong said one of the schools was burned to the ground and the other three damaged. He speculated that the arsonists may have opposed the closing down of some 400 community radio stations, many of which had been used as mouthpieces for the fallen regime.