Zimbabweans say they have been beaten up for supporting the opposition
Church leaders in Zimbabwe have called for international action to prevent post-election violence developing into genocidal proportions.
African countries and the UN should intervene to deal with a "deteriorating" situation, they said.
The opposition says it won the 29 March presidential poll outright, but results are yet to be released.
Meanwhile, a Chinese ship carrying weapons to Zimbabwe may return to China after being blocked in South Africa.
Chinese foreign ministry spokeswoman Jiang Yu said the ship's owners were considering bringing the arms back, amid international pressure not to let the ship unload its cargo.
But on Tuesday the ship was located off Africa's southernmost point, the Cape of Good Hope, and was said to be heading in a north-westerly direction.
In a joint statement, leaders of the main religious denominations warned against leaving the post-election deadlock unresolved.
"If nothing is done to help the people of Zimbabwe from their predicament, we shall soon be witnessing genocide similar to that experienced in Kenya, Rwanda, Burundi and other hotspots in Africa and elsewhere," they said.
Robert Mugabe is a liberation hero on our continent and he must be convinced to make a graceful exit
"We appeal to the Southern African Development Community (SADC), the African Union and the United Nations to work towards arresting the deteriorating political and security situation in Zimbabwe."
The opposition Movement for Democratic Change (MDC) and its leader Morgan Tsvangirai insist they beat President Robert Mugabe's Zanu-PF party outright in presidential and parliamentary polls.
An election recount for 23 out of 210 constituencies that had been due to end on Monday, has been delayed for an unknown period.
The MDC has rejected the recount as illegal.
On Tuesday Mr Tsvangirai said the Zimbabwe Election Commission had been discredited and he would not accept any run-off.
Speaking in Ghana, he appealed for help from the international community.
Zimbabwe's President Robert Mugabe has been under fire over March's disputed elections. His neighbours have been supportive but regional differences are now emerging.
South Africa's President Mbeki is the key Zimbabwe mediator. He has refused to criticise Robert Mugabe but the ruling ANC, and trade unions have urged him to take a stronger line.
Zambian President Mwanawasa has taken the region's strongest line on Zimbabwe. His call for Africa not to let a ship carrying weapons to Zimbabwe dock will outrage President Mugabe.
Angola's government has close ties to Zimbabwe's ruling party - both came to power after fighting colonial rule in the 1970s.
Botswana is not seen as an ally of Robert Mugabe. Opposition leader Morgan Tsvangirai fled here after polls.
Namibia is a close ally of Zimbabwe - it too is planning to redistribute white-owned farms to black villagers.
Mozambique has hosted some white farmers forced from Zimbabwe and is seen as relatively sympathetic to Zimbabwe's opposition.
Tanzania's ruling party has a long history of close ties to Robert Mugabe's Zanu-PF party and is unlikely to criticise him.
DR Congo's President Joseph Kabila is an ally of Robert Mugabe, who sent troops to help his father, Laurent Kabila, fight rebels.
Malawi is seen as neutral. But some 3m people of Malawian origin are in Zimbabwe, mostly farmworkers who have lost their jobs and were sometimes assaulted during farm invasions.
"Robert Mugabe is a liberation hero on our continent and he must be convinced to make a graceful exit," he said.
Mr Tsvangirai also renewed his criticism of South African President Thabo Mbeki, who has been acting as a mediator over Zimbabwe.
"We call on President Mbeki to be bold and take this historic opportunity to side with the people of Zimbabwe and not with any political party," he said.
The leader of the governing African National Congress in South Africa - Jacob Zuma - has further distanced himself from Mr Mbeki, criticising the delays in publishing the election results.
"It's not acceptable. It's not helping the Zimbabwean people who have gone out to... elect the kind of party and presidential candidate they want, exercising their constitutional right," he told Reuters news agency.
Post-election violence has displaced 3,000 people, injured 500 and left 10 dead, according to MDC secretary general Tendai Biti.
Human rights groups say they have found camps where people are being tortured for having voted "the wrong way".
But Zimbabwe's Justice Minister Patrick Chinamasa denied that anyone had died in political violence.
Police spokesman Wayne Bvudzijena was reported as saying that of the 10 people reported dead, only four names had been supplied and "of these three have no basis whatsoever while the fourth is still under investigation and will be concluded soon".
Meanwhile the fate of the Chinese ship, the An Yue Jiang, is still uncertain.
A spokesman at the Lloyds Marine Intelligence Unit in London said that according to the ship's Automatic Identifying System (AIS), it was heading up the coast of Africa, towards Angola.
Secretly filmed footage of alleged attack victims in Zimbabwe
The ship is reportedly carrying three million rounds of ammunition, 1,500 rocket-propelled grenades and 2,500 mortar rounds.
It had been anchored off the port of Durban for four days before being forced to move on Friday after a South African court refused to allow the weapons to be transported across the country to landlocked Zimbabwe.
A spokesman for the US department of state, Tom Casey, said the US had discouraged China from sending arms to Zimbabwe and had urged Mozambique, South Africa, Angola and Namibia to prevent the ship from docking.
"Right now clearly is not the time that we would want to see anyone putting additional weapons or additional materiel into the system when the situation is so unsettled and when we have seen real and visible instances of abuses committed by the security forces," he told reporters.
The MDC says the arms could be used to "wage war" on its supporters ahead of a possible run-off in the presidential election, a charge the government has strongly denied.
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