Ruling party militants occupied a farm Saturday, burning buildings and threatening its white manager in violence that came three days after Zimbabwe's government pledged to restore law and order and stop the seizure of white-owned land.

About 150 militants stormed onto Logan Lee Farm in Beatrice, 40 miles south of Harare, and threatened manager Angus Brown and his employees, said Jenni Williams, a spokeswoman for the Commercial Farmers' Union, which represents about 5,000 white landowners. Brown fled.

Police refused to respond to calls for help, and the local farmers' association advised Brown via radio to abandon the property after workers' houses were burnt, Williams said.

The attack was the first since Foreign Minister Stan Mudenge pledged Thursday to end farm occupations in return for British funding for orderly land reform.

Ruling party militants have occupied more than 1,700 white-owned farms since March 2000, spurred by a government campaign to take 4,600 white-owned farms — about 95 percent of all white-owned land in Zimbabwe — and give the land to blacks.

At least nine white farmers and dozens of supporters of the opposition to the government President Robert Mugabe have died in clashes since June.

The foreign minister's pledge came in an accord that was reached in Abuja, Nigeria, and was brokered by Nigeria with the support of Britain and other Commonwealth members.

The accord, which obliges Zimbabwe's government to uphold the law, has not been signed by Mugabe, who officials said was in Libya on a state visit.

Mugabe in the past has described the farm occupations as "a minor trespass" and a legitimate protest against unfair land ownership by the white minority.

In other discord Saturday, opposition leaders accused the ruling party of rigging a mayor election in the Western city of Bulawayo. A ruling party spokesman, Nathan Shamuyarira, dismissed the claims.

Ruling party supporters were bused in to the area to help sway the vote in favor of the ruling party candidate, said David Coltart, a spokesman for the opposition Movement for Democratic Change.

The Movement for Democratic Change, which holds 56 of the 120 elected seats in Zimbabwe's parliament, was expected to win the mayoral elections easily. Results are expected Monday.

In the Makoni East district, 100 miles southeast of Harare, where a parliamentary by-election was under way, police said five opposition supporters were arrested for beating five backers of the ruling party, state radio reported.

Mugabe has been in power for 22 years and plans to seek another six-year presidential term in elections in April, but his support has waned.