Zimbabwe police have arrested the country's most prominent rights lawyer and four senior officials with the prime minister's party, a day after the nation voted in a referendum on a new constitution that calls for more protection against human rights violations.

Rights lawyer Beatrice Mtetwa is being charged with allegedly "obstructing or defeating the course of justice" and Prime Minister Morgan Tsvangirai's chief legal adviser, Thabani Mpofu, is accused of impersonating police by compiling dossiers on unspecified crimes, a police official said on Sunday.

Mtetwa was called to an address in Harare where police were searching an office used by Mpofu and began "shouting at officers and preventing them from doing their duties", police official Charity Charamba said.

She said all of those arrested were being held for questioning on Sunday.

Police had been instructed to search the offices of a private group, the Democratic Alliance of Zimbabwe, where it was believed some information on alleged crimes was being illegally held, she said.

Police removed unspecified "exhibits" for evidence against the group that they were engaged in police-type investigations, she said. Witnesses said computer equipment and mobile phones were seized.

Pro-democracy and rights groups routinely gather witness accounts of alleged crimes and abuses of power in state institutions, including the police force, controlled by President Robert Mugabe.

Obstructing justice and impersonating police officers carry a penalty of imprisonment or a fine.

High-profile lawyer

Witnesses said on Sunday that Mtetwa demanded that police produce a search warrant at the suburban house used by Mpofu.





The approval of the draft constitution would

limit powers of President Mugabe [EPA]

Officers accused her of trying to take photographs of a security detail on her mobile phone and she was forced into a police vehicle, the witnesses said.

Mtetwa has won an array of awards from international bodies, including the American Bar Association and the European Bar Human Rights Institute, during her legal career of three decades.

She has represented Tsvangirai and his supporters in high-profile cases where she has accused police of the wrongful arrest and detention of Mugabe's perceived opponents without sufficient evidence.

Mpofu is a senior attorney who is the head of the research and development department in the prime minister's office.

Police on Sunday also raided and searched Harare offices of Tsvangirai's media and communications unit.

Three other members of Tsvangirai's personal staff were arrested on Sunday morning, the independent Zimbabwe Lawyers for Human Rights said.

They were identified as Warship Dumba, Felix Manditse and Annah Muzvidziwa, all close aides of Tsvangirai.

Constitutional referendum

Voting in a referendum on a new constitution ended late Saturday. All main party leaders called for a "Yes" vote on constitutional reforms.

A preliminary count of around half a million votes showed that more than 90 percent endorsed the draft constitution, according to Tsvangirai's party.

The proposed text would introduce presidential term limits, increase parliament's powers and pave the way for a general election to decide whether 89-year-old Mugabe stays in power.

The Southern African Development Community (SADC) described the referendum as "peaceful and credible" but condemned isolated cases of violence on the eve of the vote.

SADC observers "noted reports of isolated cases of intimidation and harassment in some areas and in particular in Mbare, Harare".

The Zimbabwe Electoral Commission said on Sunday that at least two million out of five million registered voters had cast ballots.

Full results are to be announced within five days of the vote.