Just as Tommy Miller was milking his Friesian herd early yesterday morning, the mob stormed into Dunluce Farm. Armed with sticks, stones and a shotgun, they ordered him to stop. He refused. The cows had to be milked or they would become ill. “This is the law,” replied their dreadlocked leader, brandishing his baton. “You must throw the milk on the ground.”

As they rampaged through Zimbabwe’s last productive farms, Robert Mugabe’s feared militiamen threatened to drive the country to starvation with a campaign not just to reclaim white-owned land but to destroy the farming system.

Reports flooding into farmers’ unions in Harare yesterday told of the wilful destruction of farm equipment, produce and buildings as part of an alleged “popular uprising” by government-backed mobs in the name of getting the land back for the black population. Agriculturalists fear that the country could run out of food within weeks as the farm invasions stop the maize harvest in mid-flow and threaten the future of wheat crops with only four weeks left for planting.

As of yesterday, 60 commercial farmers – including two black farmers with opposition sympathies – had been evicted from their farms by mobs of so-called war veterans, the shock troops unleashed by Mr Mugabe in a desperate attempt to cling to power. Dozens more have fled their farms, unwilling to resist the increasingly violent mobs, which have set fire to farm labourers’ huts and beaten workers.

Up to 300 veterans, in T-shirts of the ruling Zanu (PF) party, turned up at Mr Miller’s sprawling dairy farm south of Harare yesterday, closing down production when he refused to leave, and surrounding his heavily fortified house to try to flush him out.

Milk has become one of the scarcest commodities in Zimbabwe since the first invasions in early 2000, and long queues form from early morning in the rare places it can be found on sale. In a land of such desperate hunger, the wanton waste of milk seems unbelievable. But while millions of Zimbabweans spent their day in the exhausting search for food, Mugabe supporters spent theirs in a frenzied effort to destroy the supply chain.

The militias, financed by trillions of Zimbabwean dollars printed since Mr Mugabe’s apparent election defeat 11 days ago – official results have still not been announced – are answering a call to arms to defend the land from a new white invasion and reclaim what is held by the country’s few hundred white farmers. Mr Mugabe has cast the opposition Movement for Democratic Change (MDC) as the stooges of former British colonial rulers, claiming that it is seeking to hand back land to ousted whites.

When two white Times journalists drove to Dunluce Farm yesterday on the pretext of buying meat, the car was set upon by the chanting mob occupying the farm. They dragged a cart across the driveway to block an escape and gathered, chanting and mocking, round the car. “The butchery is closed, the farm is closed,” their leader said. “This is the law.”

Similar tales were told by the white farmers fleeing to Harare for safety and congregating at the offices of the Commercial Farmers’ Union (CFU) to report attacks on their farms. “They are saying they have come to reeducate the people and repossess the land,” one white farmer from Mashonaland Central said, refusing to give his name for fear of retribution.

Too afraid to return to his farm, he was fretting over what would happen to his wheat crops, which must be planted within four weeks. Other farmers were evicted or fled in the middle of the maize harvest, raising fears over how long the country could last on its food stocks. Zimbabwe needs 23,000 tonnes of maize a week to feed its population, half of which it imports. Its remaining stocks stand at just two thirds of that figure. Trevor Gifford, president of the CFU, calculated that more than 1,000 lorryloads of maize would have to be imported every week just to keep the country at subsistence level.

The political limbo, meanwhile, shows no signs of ending. Yesterday a court postponed the opposition’s petition for the release of disputed election results, as news emerged that officials had been arrested for allegedly undercounting Mr Mugabe’s vote.

There is no sign of the promised run-off between Mr Mugabe and his challenger, Morgan Tsvangirai, but every sign of a violent campaign unfolding to intimidate opposition supporters. In Harare, the queues for basic food-stuffs stretched along the pavements into the evening. “We are suffering here,” said one woman, holding her crying baby. “When will it end?”

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