HARARE, Zimbabwe (AP) -- Militant ruling party supporters invaded white-owned farms Monday, a day after President Robert Mugabe urged Zimbabweans to defend seized land, fanning fears he would stage a violent crackdown to retain power.
Invasions that began Sunday worsened with intruders entering at least 23 farms in southern Masvingo province and northern Centenary, said Trevor Gifford, president of the Commercial Farmers Union.
"In Masvingo where the police have been very cooperative, every time they remove invaders, within five, six hours they're reinvading," he told The Associated Press. "It's very apparent that this is being coordinated from higher up the chain of command."
Workers were being rounded up on the farms and forced to chant anthems in support of the ruling party, he said, and many of the farm owners had fled out of concern about their safety.
"The farmers are being told that everything on the farm is the property of those invading," he said.
Opposition leader Morgan Tsvangirai, who claims to have won the March 29 election outright, was holding meetings in neighboring South Africa Monday, the same day he issued a call for international pressure to persuade Mugabe to step down.
Tsvangirai flew out of Zimbabwe Sunday evening, said Tendai Biti, secretary-general of the opposition Movement for Democratic Change, declining to give details.
South African President Thabo Mbeki, who mediated failed pre-election talks between Tsvangirai's and Mugabe's parties, was out of the country Monday.
Zimbabwean electoral officials have yet to say whether Tsvangirai or Mugabe won the presidential election, and the two rivals have adopted sharply contrasting strategies in response.
Mugabe is already campaigning for an expected runoff on a platform of intimidation and fanning racial tension. Tsvangirai says he won, and has demanded Zimbabwean courts and the international community support him.
"We urge the International Monetary Fund, at its meeting this week, to withhold ... aid to Zimbabwe unless the defeated ex-president accepts the election results in full and hands over the reins of power," Tsvangirai wrote in an opinion piece published Monday in the British newspaper The Guardian.
"This is also the time for firm diplomacy. Major powers here, such as South Africa, the U.S. and Britain, must act to remove the white-knuckle grip of Mugabe's suicidal reign and oblige him and his minions to retire.
"How can global leaders espouse the values of democracy, yet when they are being challenged fail to open their mouths?" Tsvangirai added.
A Zimbabwean court postponed until Tuesday an expected ruling on an opposition petition to force the release of the presidential election results. Mugabe's ruling party has demanded a recount, and a further delay in the release of results.
The court did decide that it had the jurisdiction to hear the case, an aspect that had been in dispute, lawyer Alec Muchadehama said. Even that ruling will decide only whether the matter needs to be handled urgently, Biti said, arguing Mugabe's party was working to further stall the process. Zimbabwe's courts are stacked with judges loyal to Mugabe.
Tsvangirai has expressed concerns the state would mobilize the armed forces, youth brigades and war veterans to terrorize voters into supporting Mugabe in any runoff. Mugabe has been accused of winning previous elections through violence and intimidation. Scores of opponents were killed during the 2002 and 2005 campaigns.
On Sunday, Mugabe urged Zimbabweans to defend land seized from white farmers, the state-controlled newspaper said Monday.
"This our soil and the soil must never go back to the whites," Mugabe told mourners at a family funeral, referring to whites by the pejorative Shona term "mabhunu," The Herald newspaper reported. "We don't want to hear this fight is going backward."
Government officials have dismissed fears of violence.
Mugabe, 84, started the often-violence seizure of white-owned farms in 2000 after he suffered his first defeat at the polls over a referendum to entrench his presidential powers. He said the farms would go to poor blacks. In reality, many of the 5,000 seized farms went to his friends and cronies.
The seizures touched off an economic collapse in the country that used to thrive on exports of food, minerals and tobacco.
Mugabe, who has ruled since his guerrilla army helped overthrow white minority rule in 1980, has seen his popularity battered by the economic crisis.
Unofficial tallies by independent monitors show Tsvangirai won more votes than Mugabe - but fewer than the 50 percent plus one vote required to avoid a runoff.
The law requires a runoff within 21 days of the initial election, but diplomats in Harare and at the United Nations say Mugabe may order a 90-day delay to give security forces time to clamp down.
The government banned most foreign journalists from covering the elections and barred Western election observers. Several foreign journalists, including Barry Bearak of the New York Times, remained in custody Monday after being charged with "illegally observing an election without official accreditation," according to their lawyer, Beatrice Mtetwa. She said the offense carried a maximum penalty of a fine, two years in prison, or both.
Mtetwa said three judges declined Monday to hear her urgent application for the release of the journalists, who are being held at Harare's central police station. She was at the court trying to find a willing judge.