Police stopped the election campaign of Robert Mugabe's main rival in its tracks today.
Just weeks before the run-off ballot for Zimbabwe's presidency, Morgan Tsvangirai was detained at an official roadblock then told all his party's rallies across the country had been banned indefinitely.
Mr Tsvangirai's campaign to unseat Mugabe has already been hit by violence and intimidation.
The latest setback came as UN aid agencies said they were deeply concerned because aid groups have been ordered to halt operations, a move that could hamper food deliveries.
Without private aid groups impoverished Zimbabweans will be dependent on the government and Mugabe's party, both of which distribute food and other aid. And some observers fear that food may be delivered only to confirmed Mugabe supporters.
Mr Tsvangirai had been trying to campaign around Bulawayo, Zimbabwe's second largest city. He was stopped at two roadblocks, and the second time ordered to go to a police station about 30 miles away.
Two hours later he was allowed to leave and drive back to Bulawayo under police escort.
His spokesman said Mr Tsvangirai was questioned by police at the station for 25 minutes, and was told that all party rallies in the country had been banned indefinitely.
"We are dismayed that our president has not been allowed to access the Zimbabwean people at a crucial stage in this campaign," he said.
Mr Tsvangirai's Movement for Democratic Change party said police had banned its rallies out of concern for the safety of him and other party leaders.
The spokesman said the justification was "nonsense," and the ban was "a clear indication that the regime will do everything necessary to remain in power."
Mr Tsvangirai out-polled Mugabe and two other candidates in the 29 March first round of presidential voting, but did not get the 50 per cent plus one vote necessary to avoid the run-off, which is scheduled for 27 June.
Opposition and human rights groups accuse Mugabe of orchestrating violence to ensure he wins re-election amid growing unpopularity for his heavy-handed rule and the country's economic collapse.
Mr Tsvangirai said yesterday his campaign has faced many obstacles.
"As I speak, all the rallies have been banned. We have had to improvise in terms of how we access the people. And it's a very hostile environment," he said.
But he said he still expected to win at month's end.
"If Mugabe did not hear the voice in March, he's going to hear a much louder voice that people no longer enjoy their confidence in this government."
Mr Tsvangirai, who lost a 2002 presidential election that independent observers said was rigged in Mugabe's favour, had only returned to Zimbabwe in late May to campaign for the run-off. He left the country soon after the March first round, and his party has said he was the target of a military assassination plot. He has survived at least three previous assassination attempts.
Mr Tsvangirai's party says at least 60 of its supporters have been slain in the past two months.
Aid groups in Zimbabwe have been hit by an indefinite suspension of field work despite millions of Zimbabweans depending on international groups for food and other aid as the economy crumbles.
James Elder, a spokesman for the UN children's agency, said the suspension was "completely unacceptable and hugely concerning. Hundreds of thousands of children are in need of immediate assistance.
"With the onset of the winter in Zimbabwe, the timing is critical for children who are among the most vulnerable and most in need of support," Elder said.
Mugabe has led Zimbabwe since independence from Britain in 1980 and was once hailed as a liberator who promoted racial reconciliation and economic empowerment.
But he has been accused of clinging to power through election fraud and intimidation, and of destroying his country's economy through the seizure of white-owned farms beginning in 2000.