In a letter submitted to the premier's representative by leader Noparuj Vorachitwutthikul and several members, the group alleged that Sonthi had violated articles 137 and 157 of the criminal law by having two registered wives.

Noparuj said the Army chief had registered his marriage to his first wife, Sukanya, when he was a lieutenant, and later registered another marriage to his second wife, Piyada, while he was a captain.

"He now lives together with his two wives; we can prove it from many media [sources]," Noparuj said.

Noparuj produced a copy of the wedding invitation of Sonthi's son born from Sukanya and a copy of a newspaper photo showing Piyada, as president of the Army Wives' Association, receiving donations of money and basic necessities to help flood victims.

He said the junta chief's behaviour showed that he was against the law and also damaged the Army's image.

Noparuj said he would collect more evidence against Sonthi and hold a press conference after the Army chief returned from his current pilgrimage to the Muslim

holy city of Mecca in Saudi Arabia.

He refused reporters' requests to produce copies of Sonthi's marriage registrations to back his claim.

"I will show [the marriage registrations] to the public after the CNS chairman comes back," he said.