One of four men suspected of carrying out the failed July 21 London bomb attacks arrived in Britain Thursday from Italy, and was set to be charged with conspiracy to commit murder and other offences.
A private plane carrying Hamdi Issac, a 27-year-old Briton of Ethiopian origin also known as Hussain Osman, touched down at RAF Northolt, a military air base in north-west London, before 1:45 pm (1245 GMT), television pictures showed.
Shortly afterwards a convoy of police vehicles, their sirens sounding, left the airport and headed towards the city centre.
Earlier in the day, London's Metropolitan Police said they would arrest Issac on suspicion of conspiracy to commit murder, attempted murder and alleged offences under the Explosive Substances Act after he arrived.
He would then be taken to a London police station to be formally charged and would appear before magistrates on Friday at a special session convened at London's high-security Belmarsh Prison, a police statement added.
The plane left Rome's Ciampino airport shortly after midday local time (1000 GMT) after Issac was handed over to British police officers at the capital's Rebibbia prison.
Italy's highest appeals court upheld on September 13 a lower-court decision to extradite him at the request of British prosecutors.
The two-month extradition process was being seen as a test case for the new European arrest warrant, brought in to speed up extradition.