A district judge ruled yesterday that there was no legal reason to delay the extradition of four Rwandans to their own country to answer charges that they played leading roles in genocide.The men slipped into Britain under false identities after the backlash to the violence in which about 800,000 people, mostly Tutsis, were killed by rival Hutus over 100 days in 1994.

Vincent Bajinya, 46, accused of being a “category one” offender, changed his name to Dr Brown and became a British citizen, working for an East London charity helping refugees. He faces charges of organising the militia in Kigali, the Rwandan capital.

After a six-month hearing, District Judge Anthony Evans placed the matter with Jacqui Smith, the Home Secretary, in a 129-page judgment, which makes Britain less of a haven for those believed to have followed the same path.

He told the four men in the dock at Westminster Magistrates' Court: “The enormity of the scale of the killings in the genocide and the prosecution of those involved would not be appropriately dealt with in any other jurisdiction other than which was established for that purpose.”

The Home Office has already stated that those suspected of the genocide should answer charges in Rwanda.

The men were arrested in London, Manchester, Essex and Bedfordshire in December 2006 under a memorandum of understanding in which Rwanda waived the death penalty to become a temporary extradition partner with Britain.

Dr Bajinya, who settled in Islington, North London, changed his name by deed poll to Dr Vincent Brown on becoming a British citizen. He is said to have been a member of the governing MRND party and present at a meeting in 1993 where the anti-Tutsi “Hutu Power” movement was born.

James Lewis, QC, representing the Rwanda Government, told the court: “He played a high-profile role in that meeting ... The primary purpose of that meeting was to encourage Hutus to dissociate themselves from the enemy.” He is said to have later been a leader of the Interahamwe militia, which led the slaughter.

Dr Bajinya is accused of leading a party to a house where a Tutsi woman was taking refuge with her two-month-old baby. After the baby was killed Dr Bajinya is said to have questioned the woman before a militia man shot her.

Emmanuel Nteziryayo, 44, a father of five, was bourgmestre, or mayor, of the Mudasomwa commune at the time of the genocide. He gave a false name to immigration officials when he sought asylum in Britain and had been living on benefits in housing association accommodation in Wythenshawe, Greater Manchester. Charles Munyaneza, 49, of Bedford, and Celestin Ugirashebuja, 53, of Walton-on-the-Naze, Essex, were also said to be bourgmestres.

Mr Lewis claimed that Mr Munyaneza had organised the training of the Interahamwe militia to participate in the systematic massacre of the Tutsis and in a number of public speeches to spread the message that Tutsis must be killed.

The four, who are being held in Belmarsh prison, are accused of genocide, conspiracy to commit genocide and crimes against humanity. They deny the charges and are expected to continue their legal fight against extradition and could appeal to the High Court and the House of Lords.

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