A former jihadist recruiter who now seeks to deradicalise young Muslims was released without charge yesterday after being held for 12 days under the Terrorism Act.

Hassan Butt, 28, who has been offered Home Office funding to support his work, was arrested by officers from Greater Manchester Police (GMP) on May 9 as he prepared to board a flight to Pakistan. His release came as lawyers for the police appeared at the High Court to defend an attempt to force journalists to hand over materials relating to Mr Butt.

Shiv Malik, a freelance journalist who has helped the former extremist to write his autobiography, is challenging a production order obtained by the GMP against him. It requires him to give the police all his notes and source material for the book and all information in his possession concerning Mr Butt’s past activities.

The force is seeking similar production orders against the BBC, the American TV network CBS, the Sunday Times and Prospect magazine.

Mr Butt has made no secret of his past involvement in Islamist radicalism. He sent dozens of young British Muslims to training camps in Pakistan and raised large sums of money for the Taleban.

Mr Butt says he began to reassess his theological beliefs after the July 2005 suicide attacks on London, eventually repudiating violence and realising that “killing in the name of Islam, for the sake of killing, is completely and utterly prohibited”. He has since taken a public stance urging Muslims to confront the ideology that lures young people into Islamic militancy.

Mr Butt’s autobiography had been due for publication this month but its release was put on hold after the police obtained the production order against Mr Malik in March. The move is said to have followed references to Mr Butt made by a Mr A, a defendant in a forthcoming criminal trial who cannot be identified for legal reasons.

Refusal to comply with the order could lead to contempt of court proceedings and a potential two-year jail sentence for Mr Malik, 27, from North London. The author, whose past investigative work on Islamist terrorism has been widely praised, won the right to challenge the order and a two-day judicial review began at the High Court in London yesterday.

James Eadie, QC, representing Mr Malik, told Lord Justice Dyson, Mr Justice Pitchford and Mr Justice Ouseley that the subject before them was of “particular importance and concern”.

“This is a case about press freedom - the importance of that having long been recognised as vital in a democratic society, and we say this case has important ramifications.”

The hearing continues.

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