Zimbabwe police detain activists

Mr Tsvangirai has said he will return on Saturday to begin campaigning

Zimbabwean police have arrested 12 opposition supporters, state media says, as their leader Morgan Tsvangirai prepares to return to the country.

Mr Tsvangirai is to begin campaigning for a run-off presidential vote pitting him against President Robert Mugabe.

His supporters were detained on public violence charges in Mutare, the state-run Herald newspaper said.

Meanwhile, Zimbabwe's attorney-general said the violence that followed March's contested elections has begun to abate.

The presidential election run-off is due to take place on 27 June, despite warnings that election violence makes a fair second round impossible.

Opposition and human rights groups have said hundreds of opposition supporters have been beaten up and at least 40 killed since the first round on 29 March.

The ruling party denies supporting violence and says the West is trying to demonise Zimbabwe.

'Carrying weapons'

According to a police spokesman quoted in the Herald, the opposition supporters detained in the eastern border town of Mutare were carrying weapons which they were using to terrorise members of the public.

Mr Mugabe has accused the opposition Movement for Democratic Change party of fomenting violence since the disputed first round election.

Since that vote, Mr Tsvangirai has spent more than a month outside Zimbabwe, mainly in South Africa, trying to drum up international support.

He told Zimbabweans in Johannesburg that he intended to return home on Saturday to get his run-off campaign under way.

He had planned to return last week but cancelled, saying there was a plot to assassinate him.

Allies of President Mugabe said the claims were an opposition fantasy.

According to official results, Mr Tsvangirai gained the most votes in the presidential poll, but did not pass the 50% threshold needed for outright victory.

Last year, Mr Tsvangirai was treated in hospital after being assaulted by police.