Thailand ? Police say they have arrested a key protest leader on charges of insurrection against the Thai government.

Police were seen taking Chamlong Srimuang, a one-time mayor of Bangkok, at a polling station where elections for the city’s top job were beginning Saturday.

Police Colonel Sarathon Pradit has confirmed that Chamlong, leader of a monthslong protest against the government, had been arrested.

Police on Aug. 27 issued arrest warrants for nine protest leaders on a variety of charges including insurrection, which carries a maximum penalty of death or life imprisonment. On Friday, another key figure was arrested on the same charges.

The nine led mass street demonstrations that brought down the government of Prime Minister Samak Sundaravej last month.