Morgan Tsvangirai, the leader of Zimbabwe’s main opposition party, has vowed to keep fighting against the brutal regime of Robert Mugabe, as he left hospital in a wheelchair after suffering what he described as an “orgy of heavy beatings” at the hands of police.

Mr Tsvangirai, the head of the Movement for Democratic Change (MDC), has been treated for what his party said was a suspected skull fracture since Tuesday, two days after he and scores of supporters were arrested in a protest against the President. He said the assault by authorities left him feeling as if he had been “partially decapitated”. Doctors have not confirmed a fracture.

But despite his ordeal, he insisted said that democratic change in Zimbabwe was “within sight”, appealing to the international community for help in overturning the regime. “They brutalised my flesh. But they will never break my spirit. I will soldier on until Zimbabwe is free,” he said.

The comments came as Britain stepped up its criticism of the President, accusing him of action “bordering on crimes against humanity” in his attempts to suppress dissent.

Yesterday, Mr Mugabe told his critics in the West that they could “go hang” as he intensified a crackdown against rising opposition to his rule.

Human rights workers spoke of an “ad hoc state of emergency” in a large swath of Harare’s volatile southwestern townships, where hundreds of police were deployed, attacking ordinary people at random.

“The number of people being badly beaten up is very high,” said a private doctor who asked not to be named. “We’re only seeing a tiny proportion of it. People are terrified of leaving their homes at night.”

As opposition militants showed that they were prepared to meet violent repression with increasing retaliation, concern was growing last night that Mr Mugabe may declare a state of emergency that would strip what is left of the curbs on him. Unofficial reports said that the issue had been discussed at Cabinet and in the politburo of his ruling Zanu (PF) party this week.

The southwestern townships have been the focus of a ferocious operation to squash dissent since February 25, when police defied a court order to allow the opposition MDC to hold a rally. The move set off a violent reaction from opposition activists, culminating in the savage three-hour assault on Sunday of Mr Tsvangirai and 30 of his lieutenants and supporters.

Images of the opposition leader entering hospital earlier this week, badly bruised and limping, fuelled international outrage and threats by the US and other nations to strengthen sanctions against Mr Mugabe and his immediate coterie.

Following his discharge from the private Avenues Clinic, the MDC leader is expected to take rest at home. “He is still swollen and in pain, but he feels it’s better to recuperate from home ... he is still not himself,” a spokesman told Reuters, adding that Mr Tsvangirai was still suffering from dizziness.

Writing in The Independent, Mr Tsvangirai said the ordeal had made him even more determined to continue his campaign. “Democratic change in Zimbabwe is within sight. Far from killing my spirit, the scars they brutally inflicted on me have re-energised me,” he said.

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