Bangkok - Thai police on Friday arrested one of nine leaders of the protest movement that has occupied government headquarters for the past 39 days and detained him to face treason charges.

Chaiwat Sinsuwong, a leader of the People's Alliance for Democracy (PAD) that stormed Government House with thousands of followers on August 26 and have occupied the seat of the executive power since, was arrested as he left the house of Thai politician Kraisak Choonhavan, a member of the opposition Democrat Party.

Chaiwat and eight other leaders of the PAD have been charged with treason, for which the maximum penalty is death.

The PAD is a loose coalition of groups staunchly opposed to the return to power of former prime minister Thaksin Shinawatra and his political cronies.

Thaksin, a billionaire former telecommunication tycoon who won unprecedented mass support during his two-term premiership between 2001 to 2006 by introducing populist policies aimed at the poor, was outed by a military coup on September 19, 2006.

The PAD played a key role in organizing mass demonstrations against Thaksin in 2006 that culminated in his downfall.

The movement took to the streets again in May this year when it became obvious that the government of former prime minister Samak Sundaravej was pushing for constitutional amendments that might have led to a political comeback of Thaksin and 110 of his close political allies who have been banned form politics for five years.

Samak, a close political ally of Thaksin's, lost his job last month after the Constitution Court found him guilty of moonlighting on the premiership by hosting television cooking shows.

He has been replaced by Somchai Wongsawat, Thaksin's brother-in-law.

Unlike Samak, Prime Minister Somchai has adopted a conciliatory approach to the PAD and may include them in talks on how to amend the constitution to pave the way for political reform.

It was Samak who persuaded police to charge the PAD leaders with treason for seizing Government House. The charge has been highly criticized for being too extreme. (dpa)