The UN warned on Tuesday that post-election violence in Zimbabwe was rising to near crisis levels ahead of a planned presidential run-off, with opposition supporters bearing the brunt of attacks.
As opposition leader Morgan Tsvangirai prepared to return home to contest the election against President Robert Mugabe, his hopes the ballot would be held later this month in a peaceful atmosphere appeared to be wishful thinking.
With Tsvangirai's Movement for Democratic Change claiming 32 of its supporters have been killed since voting on March 29, the United Nations resident representative in Zimbabwe said most of the violence was directed against followers of the opposition, although the MDC was not blameless.
"There is an emerging pattern of political violence inflicted mainly but not exclusively on rural supporters of the MDC," Agustino Zacarias told reporters, adding that there were "indications that the level of violence is escalating ... and could reach crisis levels."
Announcing plans to return home this week, Tsvangirai said at a news conference on Saturday that he would only participate in the run-off if there was a complete end to unrest.
He also called for a revamp of the electoral commission and the deployment of international peacekeepers and foreign observers, but these demands have been brushed aside by the government.
"The United Nations country team urges all political leaders across the political divide to unequivocally renounce politically-motivated violence," added Zacarias, a Mozambican diplomat.
Mugabe's government has been intensifying a crackdown on its opponents in recent days, with police arresting an opposition lawmaker for the first time on Monday.
Heya Shoko, a Movement for Democratic Change (MDC) parliamentarian who won a seat in Masvingo province formerly held by Mugabe's ZANU-PF party, was arrested in connection with post-election violence in his constituency.
Journalists, union leaders and hundreds of political activists have been arrested since general elections in March that were lost by the ruling party.
MDC leader Tsvangirai is expected to return home by the weekend and will address an opposition rally on Sunday to kickstart his campaign to unseat Mugabe, an aide said on Tuesday.
"We are certainly going back this weekend. We may even be back before then," George Sibotshiwe told AFP.
The United States has called for Mugabe's government to guarantee the safety of Tsvangirai – who is threatened by a treason charge and was badly beaten in police custody in March last year – when he arrives back in Harare.
The authorities should allow in international media as well as provide "some type of security and guarantees for Morgan Tsvangirai's safety," Jendayi Frazer, the US assistant secretary of state for African affairs, told reporters.
The government has said the MDC leader had no reason to fear for his safety.
"If indeed there was a threat to his life, we have got law enforcement agents," Bright Matonga, the deputy information minister, told AFP on Monday.
Results from the first-round presidential poll were delayed by the electoral commission for five weeks and no date has been given for the run-off even though the law says it should take place within 21 days of the first-round results being announced.
Mugabe, in power since the country's independence in 1980, lost by 43.2 per cent to 47.9 per cent to Tsvangirai in the first presidential poll.
A one-time regional role model, Zimbabwe's economy has been in meltdown since the start of a land reform programme at the turn of the decade which saw thousands of white-owned farms seized.
Inflation now stands at over 165,000 per cent, unemployment at more than 80 per cent and even basics such as cooking oil and bread are in scarce supply.