Police used tear gas on Saturday and arrested about 100 protesters attempting to break through roadblocks to reach the site of an anti-government demonstration in Bangkok.
Police threw tear gas into a truck carrying demonstrators as it attempted to push through a barricade on Ratchdamnoen Avenue leading to the Royal Plaza site of the protest.
“We tried to solve the confrontation peacefully but had to resort to using tear gas when they refused to retreat,” National Police Bureau spokesman Police Major General Piya Utayo said.
He said seven policemen were injured by the truck as it rammed the barricade.
Police arrested about 100 of the demonstrators who trying to reach the protest site, Mr Piya said.
Parts of Bangkok have been placed under the Internal Security Act since Thursday, in an anticipation of violence during the rally organized by the pro-royalist Pitak Siam movement, led by retired Army General Boonlert Kaewrasit.
“The police overreacted and have now harmed the people,” Mr Boonlert said, addressing a gathering crowd outside Parliament.
Pitak Siam, a newcomer at least in name to Bangkok’s street protest movements, attracted about 20,000 followers to its first rally in October, surprising the government with a strong turnout.
“A lot more people came to the October 28 rally than was expected so now they need to keep the momentum going by staging another one,” Chulalongkorn University political scientist Thitinan Phongsudhirak said.
He described the Pitak Siam movement as “an updated anti-Thaksin coalition,” a reference to former prime minister Thaksin Shinawatra, the de facto leader of the ruling Pheu Thai party.
Mr Thaksin, a populist politician who was ousted by a coup in September 2006, has a strong following among many rural and urban poor but he has antagonized the country’s establishment.
Ahead of Saturday’s rally, officials placed the Royal Plaza district including Parliament, Government House and the United Nations headquarters under the internal security act through next week, allowing authorities to make arrests without charges.
An estimated 20,000 police were deployed to the area.
Mr Boonlert hoped to attract at least 50,000 protesters on Saturday. The group claims the government of Prime Minister Yingluck Shinawatra is against the monarchy and corrupt.