HARARE (AFP, REUTERS) - Zimbabwe President Emmerson Mnangagwa, a former ally of Robert Mugabe, narrowly won the country's landmark election, results showed early Friday (Aug 3), in an outcome set to fuel fraud allegations as security forces patrolled the streets to prevent protests.

The opposition says it will challenge election result in court.

Mnangagwa won 50.8 per cent of the vote, ahead of Nelson Chamisa of the opposition MDC party on 44.3 per cent, the Zimbabwe Electoral Commission (ZEC) said.

"Mnangagwa, Emmerson Dambudzo, of ZANU-PF party is therefore duly declared elected president of the Republic of Zimbabwe," announced ZEC chair Priscilla Chigumba.

Mnangagwa needed more than 50 per cent of the vote to secure victory without a second-round run-off.

He quickly took to Twitter to say he was "humbled" to have won the election, hailing it as a "new beginning" for the country.

Before the results announcement, both men had expressed confidence in victory, and international observers urged speedy release of the outcome to avoid further violence after clashes between security forces and opposition supporters.

The election, the first since the army's removal of 94-year-old Mugabe, passed off relatively smoothly but its aftermath revealed the deep rifts in Zimbabwean society and the instinctive heavy-handedness of the security forces.

On Thursday, troops cleared the streets of the capital, despite calls from foreign governments and international organisations for calm and for political leaders to show restraint.

Police then sealed off the headquarters of Chamisa's Movement for Democratic Change (MDC) before storming the building and arresting 16 people.

The search warrant said they were looking for unlicenced firearms, grenades and stones. Six people were killed on Wednesday when troops fired live rounds against MDC demonstrators alleging the vote had been rigged.

CLASHES

Coupled with video of soldiers opening fire on unarmed demonstrators on Wednesday, the raid does serious damage to Mnangagwa's efforts to rehabilitate the image of a country synonymous with political repression and economic collapse.

Questioning the independence of the judiciary, Chamisa said he was reluctant to go to court to challenge the results, saying this would be "going into the lion's den".

"We are not about to be a meal for lions," he told reporters, alleging that Mnangagwa's ruling ZANU-PF party had rigged the poll but without providing any concrete evidence.

Wednesday's crackdown by the army crushed the last vestiges of euphoria that followed its removal of Mugabe in November and fuelled suspicions that the generals who launched the coup remained Zimbabwe's de facto rulers.

In Harare, the contrast could not have been starker with November, when hundreds of thousands filled the streets, hugging soldiers and celebrating their role in ousting Mugabe, the only leader Zimbabwe had known since independence in 1980.

"They are showing their true colours now. We thought they were our saviour in November but they fooled us," said newspaper vendor Farai Dzengera, saying that the brief dream of an end to decades of repression was over.

"What can we do?... They run this country."

Before the police stormed the MDC headquarters, Secretary General Douglas Mwonzora said 27 party workers carrying out voter tabulation were locked inside its offices by officers who had sealed off the building.

"We will not recognise that search warrant because they want to plant evidence. They want to disrupt our results tabulation process, that's all," he said.

Police denied the allegation. "The police are there to do their job," police spokeswoman Charity Charamba said.

Nearly all shops in downtown Harare were shuttered and the normally bustling pavements quiet the day after the bloodshed.

Mnangagwa's spokesman, George Charamba, insisted that Thursday was a normal working day. "They must go about their business as always," he said on state television.

ARMY IN CHARGE

Wednesday's violence and the use of soldiers to control the capital confirms suspicions that the generals who ousted Mugabe - including army chief-turned vice-president Constantino Chiwenga - are firmly in charge, analysts said.

"Deployment of troops reveals the uncomfortable truth that, eight months after Mugabe was ousted, the army remains the pre-eminent political force," said Piers Pigou, a Zimbabwe expert at the International Crisis Group think-tank.

The election was supposed to confirm the legitimacy of the post-Mugabe government and allow Harare to renew ties with the international community.

This in turn would have allowed it to start unlocking the donor funding and investment needed to get its economy - at independence, one of Africa's most vibrant - back on its feet.

Instead, observers from the Commonwealth, a group of mainly former British colonies that Mnangagwa had hoped to rejoin, did not mince words in condemning the military's conduct.

"We categorically denounce the excessive use of force against unarmed civilians," former Ghanaian president John Mahama said on behalf of the Commonwealth.

The United Nations and European Union both urged restraint, while Britain, a supporter of the "new" post-Mugabe Zimbabwe, said it was "deeply concerned" by the violence. China said however it believed the election had generally been orderly.

Mnangagwa, a long-term Mugabe aide nicknamed 'The Crocodile', offered his condolences to families of the victims of the crackdown and said those responsible would be brought to justice.