Zimbabwe's burgeoning political crisis has claimed its first victim, an opposition activist stabbed at his homestead by members of Robert Mugabe's party.

The main opposition, the Movement for Democratic Change (MDC), confirmed the man's death as it called today for a general strike after losing a High Court bid to force the immediate release of results from the presidential election two weeks ago.

"We are sad to inform you that we have lost one of our members...who passed away on Saturday after being stabbed by Zanu-PF supporters at his homestead," Thokozani Khupe, the MDC vice-president, told reporters.

Police said that the killing did not appear to be political.

The MDC says that its leader, Morgan Tsvangirai, won that election and had hoped to force the Zimbabwe Electoral Commission (ZEC) to publish the figures to back that up.

"We are calling on the public to speak against ZEC for failing to release the results," Ms Khupe told reporters. "We have called for a mass stay-in, starting tomorrow, until the results are released."

Ms Khupe was speaking shortly after Justice Tendai Uchena turned down a petition by the party that he order the electoral commission to end its silence over the March 29 election.

In her news conference, Ms Khupe said that it had now been proved that voting on its own was not enough to bring about a regime change and accused Robert Mugabe’s Zanu (PF) party of trying to use the delay since the elections to fix the result.

"We are receiving information that the ballot boxes are being kept by Zanu (PF), that they have been stuffing more ballot papers," she said. "What we want is for ZEC to announce the results. We hope every Zimbabwean takes it upon themselves to speak out and be heard.

"Voting alone was not enough. We want our results, the time has come."

The MDC had hoped that the court – although stacked with Mugabe loyalists – would force the election commission to release the results. The commission, which has already published results for parliamentary and local elections held the same day, said it was delaying the release of the presidential results so it could verify the votes.

The court rejected the opposition demand and accepted the election commission’s explanation that it was investigating anomalies in some of the voting districts, calling it "legally valid" in its ruling. "It can therefore justify the delay," it said in its ruling.

As the crisis deepens, Mr Tsvangirai remains in South Africa, where he has been trying to pressure the government to adopt a harder line against Mr Mugabe. President Thabo Mbeki of South Africa has argued that confronting the veteran Zimbabwean strongman could backfire - and other regional leaders have followed his lead.

But Mr Mbeki is reportedly under increasing pressure to show results, and some in his party have called for firmer action.

A summit of regional leaders in Zambia at the weekend failed to demand the immediate release of results or to condemn Mr Mugabe, as the opposition had hoped. Instead, the leaders said the results should be verified quickly and in the presence of the candidates or their agents "within the rule of law."

Mr Mugabe did not attend the summit.

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