Zimbabwe Energy Minister Elton Mangoma arrested
Zimbabwe's Energy Minister Elton Mangoma has been detained by police, for unspecified reasons.
Mr Mangoma is a founder of the Movement for Democratic Change, which has been in an uneasy coalition with President Robert Mugabe's Zanu-PF since 2009.
He was escorted from his offices by three plain-clothes officers.
The arrest has been condemned by the MDC and comes as its relations with Zanu PF worsen, ahead of elections planned for later this year.
A police spokesman could not confirm whether Mr Mangoma had been arrested or was just being questioned, and no reasons were given for his detention.
Reports say the arrest is believed to be in connection with a fuel deal the minister made in December with a little-known South African company.
Zanu-PF lawmakers accused Mr Mangoma of bypassing tender procedures and also claimed that only a fraction of the fuel paid for had actually been delivered.
He denies any wrongdoing and says all the fuel was delivered.
The arrest also comes as a government rifts grows over Zanu-PF plans to force foreign companies to cede a majority shareholding to Zimbabweans.
MDC leader and Prime Minister Morgan Tsvangirai has dismissed a claim from a Zanu-PF minister that the government had reached an agreement, with the regulations to be published on Friday.
Separately, the Supreme Court has nullified the election of MDC chairman Lovemore Moyo as speaker of parliament, following a legal challenge by a close ally of Mr Mugabe, Jonathan Moyo (no relation).
Jonathan Moyo argued that the 2008 election of his namesake was chaotic and disorderly, reports the AFP news agency.
Roy Bennett acquitted
The MDC and Zanu-PF agreed to share power after disputes over the 2008 poll, which saw many thousands of MDC activists forced from their homes by pro-Mugabe militias.
The MDC won a majority of seats in parliament but Mr Tsvangirai pulled out of the presidential run-off, saying he wanted to save his supporters' lives.
The Supreme Court also ruled that treason charges against senior MDC official Roy Bennett be dropped.
He was arrested in 2009, after he had been named as the MDC's nominee as deputy agriculture minister in the unity government.
He is a white farmer whose land has been seized under Mr Mugabe's land reform programme.
He told the BBC that he is unlikely to be able to take up his ministerial post as two further charges of contempt of court and perjury have been brought against him in what he says is a campaign of intimidation led by Zanu PF.
In 2004, he was jailed for pushing a Zanu-PF minister in parliament.