British police say they are investigating whether radical Muslim preacher Abu Qatada wrote extremist material while on bail fighting extradition.

The British government has been trying for years to deport Abu Qatada to Jordan, where he was convicted in absentia for terror plots. The cleric has been described by prosecutors as a key al-Qaida operative in Europe.

Abu Qatada, whose real name is Omar Mahmoud Mohammed Othman, was arrested March 8 for allegedly breaching a bail condition that prohibits him from having mobile telephones switched on in his house while he is present.

Deputy Assistant Commissioner Stuart Osborne said Thursday that police had searched the preacher's house and were investigating material in several languages to determine "whether the publications were written by Qatada."

He said no arrests had been made.