By-election test for Mugabe

Tsvangirai's MDC won Bikita West in June

The vote count is now under way following a key by-election at the weekend in south-eastern Zimbabwe after a campaign marred by violence and intimidation.

The opposition Movement for Democratic Change (MDC) was defending the seat of Bikita West, which it won by a narrow margin in general elections last June.

Officials said the vote had been completed largely without incident, and with a sharp drop in turnout on the second day. First results are expected on Monday.

The by-election is being widely seen as a foretaste of the campaign for presidential elections due next year, providing a grim warning of more political violence and instability to come.

The poll became necessary when the incumbent MP died of cancer three months after the general election.

Both the government and the opposition have attached much importance to winning the seat.

The opposition wants to prove that it can hold on to the remarkable gains it made during last year's general elections.

For its part, the ruling Zanu-PF is keen to demonstrate that its controversial land redistribution efforts are winning back support in rural areas, which are home to the majority of the population.

Troubled campaign

One ruling party member was killed, and hundreds of opposition sympathisers fled their homes during the campaign.

Government supporters and members of the War Veterans' Association continued to occupy several polling stations in the rural constituency of Bikita West on the eve of voting, raising fears that the poll will not be free and fair.

Foreign diplomats based in Zimbabwe were denied accreditation as election observers.

BBC Harare correspondent Grant Ferrett says that given the scale of intimidation, the chances of the opposition retaining the seat appear slim.

The MDC nevertheless adopted a forceful stance during campaigning, saying it would not allow its members to be beaten into submission by government supporters led by the War Veterans' Association and Zanu-PF's Youth Brigade.