British police have arrested the opposition Conservative Party's immigration spokesperson over alleged leaks of information he made public.
Media reports say Damian Green was arrested by London police at his home in Kent, southeast of London, and his offices were searched.
The leaked information is said to have come from the Home Office.
The Conservatives have been unavailable for comment on the allegations, but the arrest was condemned by the party's shadow chancellor, George Osborne.
Mr Osborne called the police decision to arrest Mr Green "absolutely extraordinary", saying MPs routinely received information from civil servants.