It was midnight on Sunday and Sylvia was fast asleep when the white pick-up truck pulled up outside her house. Barging their way in, ten men dragged her, her sister and aunt from their beds and into the back of the vehicle. “Your man did not win this election,” one shouted at her. “Next time you must get it right or you will die.”

Sylvia, a youth volunteer for the opposition Movement for Democratic Change (MDC), noticed that there were no numberplates on the vehicle — typical of those used by the Central Intelligence Office, President Mugabe's secret police. As they bounced along the road, the men set about tying the women's wrists and ankles. The truck stopped outside town and the women were pulled out on to the street and their bound hands tied to the tow bar.

Then the truck sped off again, dragging the women behind them, their flesh scraping on the tarmac. Sylvia remembers only the searing pain in her shoulder and breast before she passed out. “This is a war,” she heard them shouting. “We will keep fighting until we win.” She was dumped on a roadside and it was three days before she received hospital treatment for her wounds, which had become infected.

Sylvia's story is only one of scores emerging from the terrorised Zimbabwean countryside, where joy at the opposition election victory has turned to fear and violence. Unwilling to allow Mr Mugabe to slope off to retirement and immunity, the military has taken the reins, unleashing an orchestrated campaign of terror against opposition activists, election observers and ordinary voters in an attempt to secure Mr Mugabe victory in a second-round poll. The results lists posted outside polling stations that made massive rigging impossible are now being used to target those areas that voted “the wrong way”.

Areas across Matabeleland, Masvingo and Manicaland, which swung away from the ruling Zanu (PF) party for the first time, have found themselves at the forefront of the brutality.

White-owned farms were the first targets of the Zanu (PF) youth militias and so-called war veterans but from there the militias have moved on to party activists and even independent election observers. Insiders say that the campaign is being co-ordinated by 200 handpicked military and intelligence officers, each of whom is responsible for regional militia cells.

On Tuesday in Matabeleland South, to the east of Bulawayo, youth militia armed with AK47s stopped traffic and ordered people off buses, rounding them up and forcing them at gunpoint to chant slogans in praise of the ruling party. If they could not, they were beaten. “There will be a rerun for the presidential election and if you try and vote for the MDC again we will go to war,” the militiamen said. “We are not asking you to vote Zanu, we are ordering you - or else you will be killed.”

In Nyamuya Zoka, militiamen rounded up people from a market and marched them to a rally at which they were forced to pledge that they would vote for Mr Mugabe — “or you will die”. In the past two days the violence has become more targeted, aimed at party polling agents and observers from the Zimbabwe Election Support Network, an independent monitoring group.

On Wednesday in Seke Chintungwiza, a township south of Harare, 180 people went from house to house with a list of MDC polling agents, demanding that they be handed over. In Nyansa, in the east of the country, youth militia set upon a group of observers, beating them and warning them not to return for the second round.

Human rights groups believe that these cases represent the tip of the iceberg, with many victims too afraid to report assaults, especially to police who may be involved. In Masvingo, where four polling agents were beaten severely, a doctor refused to treat the victims for fear that he, too, could be attacked. “What we are seeing is escalating. It can only get worse,” one human rights worker said.

Next week Zimbabwe celebrates Independence Day, a reminder of the liberation war fought against white rule and a key date for the military and for war veterans, who appear to have taken control of the country in what the Opposition is now calling a de facto coup. “The military hardliners are furious that they didn't use violence and intimidation before like they did in the last two elections,” an informed source said. “Now it's a case of better late than never.”

The MDC declared yesterday that it was no longer willing to take part in a second election and called on Southern African leaders, meeting in Zambia this weekend, to force Mr Mugabe to step down before the violence worsened. “The lives of all pro-democracy actors are not safe,” Tendai Biti, the MDC secretary-general, said.

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