Riot police have clashed with protesters in the Bangladeshi capital, Dhaka, during an opposition rally.
The opposition is demanding electoral reforms
Opposition leaders say at least 50 protesters were injured when police charged with batons and used tear gas to break up the demonstration.
The opposition alliance of 14 parties, led by the Awami League, organised the protest demanding a more independent election monitoring body.
Elections in Bangladesh are due early next year.
The BBC's Waliur Rahman in Dhaka says this was one of the fiercest clashes between opposition activists and the police in recent months.
The clashes erupted as hundreds of supporters of the 14-party opposition group tried to push through police barricades in their attempt to lay siege to the Election Commission headquarters in the capital.
Some activists burned a bus in the busy central area during the protest .
Opposition leaders say some of the injured were women, who were treated brutally by the police.
Police denied allegations of using excessive force to disperse the protesters.
The opposition group, led by former Prime Minister Sheikh Hasina, organised the protest to compel the government to make the Election Commission more independent, ahead of elections due early next year.
They were seeking the resignation of the chief election commissioner and revision of a new voter list that they say is biased in favour of the government.
Last month, Sheikh Hasina unveiled in parliament some reform proposals calling for changes to electoral rules.
She said the reforms were vital to ensure that the next elections were free and fair.
Prime Minister Khaleda Zia initially refused to concede to the opposition demands, but later offered to form a bipartisan committee to examine the reform proposals.