"We deplore the acts of intimidation and unlawful violence from all parties that have taken place in recent weeks and the arson attacks on public buildings, including schools and colleges, which have been reported over the weekend," Warsi, an official at the British Foreign and Commonwealth Office, said in a statement Monday.
The Bangladesh Daily Star reported Sunday elections, the 10th since independence from Pakistan in 1971, were the country's bloodiest. At least 18 people were reported dead in election-related violence.
CNN reported police fired tear gas at protesters who tried to attack polling stations. The report said the capital of Dhaka was largely peaceful and voter turnout was low.
The Bangladeshi newspaper reported the ruling Awami League emerged victorious in the 147 of the 300 constituencies where polling was conducted.
More than a dozen opposition parties, led by the Bangladesh National Party of former Prime Minister Khaleda Zia, boycotted the weekend contest.