Arthur Mutambara was speaking from the audience at the World Economic Forum on Africa in Cape Town a day after MDC leader Morgan Tsvangirai was held by police for campaigning in the second round of presidential elections on June 27.

Tsvangirai was detained for questioning for around nine hours with several other party officials while campaigning in the west of the country. He was released Wednesday night without charge, his spokesman George Sibotshiwe said.

Harassment of MDC members has intensified in the run-up to the June 27 election that pits Tsvangirai, 56, against Mugabe, 84, for leader for the second time in three months.

Tsvangirai took more votes than Mugabe in the first round of voting on March 29 but not enough, according to the official results that were held back for five weeks, for an outright win.

The MDC says over 60 of its supporters have been killed in attacks by pro-Mugabe militia and dozens of its members arrested.

"He is trying to destroy the capacity of the opposition," Mutambara said of Mugabe, adding, in response to a question, that the MDC would not recognize a Mugabe run-off victory that had been achieved through 'genocide.'

Mutambara, leader of a smaller MDC faction that broke away from Tsvangirai in 2005 but reunited with Tsvangirai's faction in April, was arrested last weekend over an a newspaper article he wrote criticising the government and a High Court decision.

He has been charged with contempt of court and giving false information prejudicial to the state.

On Wednesday African leaders received a dressing down from Kenyan Prime Minister Raila Odinga over their handling of Zimbabwe's election crisis.

"It's unfortunate that in an African country elections can be held and no results are announced in more than a month," he said at the Cape Town conference.