Workers armed with sticks, rocks and Molotov cocktails clashed with armed police in the capital Phnom Penh.

Deputy police commissioner Chuon Narin confirmed three people died and two others were injured.

The workers are part of a nationwide strike demanding a doubling of the minimum wage to £97 a month.

Prime Minister Hun Sen faces a growing challenge to his almost three-decade rule from protesting textile workers and opposition supporters demanding that he step down and call a new election because of alleged vote fraud.

Opposition leader Sam Rainsy denounced the crackdown.

"It's an unacceptable attempt to break not only a worker strike but the whole worker movement as well as the democratic movement which is developing in Cambodia following the July elections," he said.

Human rights activist Chan Soveth, of local rights group Adhoc, who was at the scene of the clashes, said as many as 10 striking workers were badly injured.

Security forces "used rifles and other things to crack down on the strikers," he said. "They beat them on their heads."

Military police spokesman Kheng Tito said the crackdown came after nine policemen were injured by missiles.

"We were afraid about the security so we had to crack down on them," he said. "If we allow them to continue the strike it will become anarchy."

Disputes over wages and safety conditions are common in Cambodia's clothing industry which supplies brands like Gap, Nike and H&M.

The sector employs about 650,000 people and is a key source of foreign income for the impoverished country.