Security forces and opposition protesters have clashed at an opposition rally in Cambodia's capital, leaving about 40 people injured, AP reported.
City Hall official Khun Sreng said most of the injured were from the security forces. Civilian security auxiliaries are often employed by the government to break up protests.
Police arrested three lawmakers from the opposition party who led the protest to demand that Phnom Penh's Freedom Park be reopened to the public.
City authorities imposed a ban on public demonstrations in January and closed Freedom Park, which is now surrounded by razor wire, after a spasm of political violence.
The opposition claims that last year's general election was rigged and the Cambodia National Rescue Party robbed of victory. Its lawmakers have boycotted their seats in the National Assembly.