Zimbabwean police have raided a house used by senior members of the party of Morgan Tsvangirai, the country's prime minister, in an alleged search for weapons, a senior party official has said.

Tendai Biti, the secretary-general of the Movement for Democratic Change (MDC), said police entered the house in a suburb of Harare, the capital, late on Friday.

Speaking on Saturday, Biti said: "Last night, armed police numbering over 50 raided this residence on the pretext that they were looking for arms stolen from the police or the army.

"[They] ransacked every room and took a bunch of valuable party material from a room occupied by our organising secretary Morgan Komichi.

"They beat up the wife and sister of the caretaker before they started digging part of the garden ostensibly in search of weapons."

Wayne Bvudzijena, a police spokesman, had no immediate comment, The Associated Press news agency reported.

MDC boycott

The raid came just over a week after the MDC announced it would boycott cabinet meetings with the Zanu-PF party of Robert Mugabe, Zimbabwe's president, its partner in the unity government.

Tsvangirai has said he has not quit the government, but will resume unity relations only once issues - including disputes over key posts and a crackdown against his supporters - are settled.

Biti blamed Friday's raid on members of Zanu-PF and security forces opposed to the unity government.

"We regard this as further evidence of lack of a paradigm shift on the part of Zanu-PF to treat us as an equal partner," he said.

"We regard it as serious evidence of a few in Zanu-PF and 'securocrats' who want us out of the government."

Political tensions in Zimbabwe have also been heightened by the renewed detention of Roy Bennett, a white aide to Tsvangirai, on "terrorism" charges.

Bennett is is due to go on trial on November 9.