The British police have arrested three men, including the prominent Muslim cleric, Abu Hamza al-Masri, under the Prevention of Terrorism Act.
The Yemeni authorities have said they'd like to see Mr Masri extradited, or put on trial in Britain, on matters arising from two trials already under way in Yemen.
One of the trials deals with the kidnapping of Western tourists in December, and the other relates to an alleged plot to carry out acts of sabotage in Yemen.
Mr Masri's son and step-son are among eight Britons currently on trial charged with involvement in the alleged plot. The Britons' lawyers have said the arrest of Mr Masri will not affect their clients' case. Mr Masri who is from Egypt and fought with the mujahadeen in Afghanistan is the imam of a mosque in north London.
A spokesman for his group, the Supporters of the Sharia, said that Mr Masri was innocent and merely a Muslim scholar.
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