A former Rwandan army officer accused of genocide and crimes against humanity has been remanded in custody after appearing in court in London.

Lieutenant Colonel Tharcisse Muvunyi is wanted by the International War Crimes Tribunal in connection with Rwanda's 1994 genocide, in which hundreds of thousands were killed.

He was arrested in London on Saturday. He has lived in the United Kingdom since March 1998.

Mr Muvunyi's lawyer told Bow Street magistrates that his client was the man named on the tribunal's charge sheet, but was not guilty of the crimes which it described.

A police officer asked the court that he be remanded in custody as there was a chance of him absconding.

Mr Muvunya's lawyer requested bail for his client, arguing that there was nowhere Mr Muvunya could flee to.

But the magistrate said there were substantial grounds for rejecting bail.

He said Mr Muvunyi would be kept in custody, before being handed over to the War Crimes Tribunal for Rwanda.

He said the colonel had 15 days to appeal.

Investigations

Asked why it had taken so long for the arrest warrant to be issued, tribunal spokesman Kingsley Moghalu said a "thorough and very rigorous investigation" had been conducted.

"Those investigations had to be completed before the tribunal could request the government of Britain to have him arrested," Mr Moghalu told the BBC's World Today programme.

A UK Home Office spokeswoman said the authorities in London had notified the tribunal of Mr Muvunyi's presence in 1998.

He was arrested in Lewisham, south London, by officers of Scotland Yard's Organised Crime Group extradition unit on Saturday.

As a UN member state, the UK is obliged to hand over Mr Muvunyi at the request of the tribunal.

The procedure is not the same as an extradition request by another state, and bypasses the often lengthy processes of appeal which apply in the case of an extradition.

Mr Muvunyi's only legal recourse is to apply for a writ of habeas corpus, which will result in the case being transfered to the high court.

UK Foreign Secretary Robin Cook said he was pleased that the UK was able to respond quickly to the tribunal's request.

"This is more evidence of our determination to support the International Criminal Tribunal in Rwanda in its work to bring the perpetrators of crimes against humanity to justice," Mr Cook said.

Prime suspect

Colonel Muvunyi, 46, was the senior army officer in the Butare region of southern Rwanda under the previous Hutu-dominated regime.

In April 1994, he is alleged to have signed an order requiring nuns to release 25 Tutsi children they were shielding in a convent after their parents had been butchered.

Soldiers forced their way into the convent and the children were loaded onto lorries, never to be seen again.

The colonel is a prime suspect, wanted not only by the UN tribunal set up to investigate and try those responsible who escaped the country, but also by Rwanda, which has published 17 indictments alleging genocide and crimes against humanity.

Human rights workers say that the crimes committed at Butare could not have happened without the connivance and co-operation of the army, which provided transport and arms.

A total of about 100,000 people are thought to have died in the area.

Mr Muvunyi was granted temporary political asylum after arriving in the UK. He has been living in London with his wife and three children.

The colonel has been quoted by one newspaper as saying that he tried to keep the region calm, but that it became impossible to stop the slaughter.

Mr Muvunyi, who has been living on social security and working for a charity, was last year given permission to stay in Britain until 2002.