French authorities on Thursday authorised the release of Julien Coupat, who has been detained for more than six months on suspicion of sabotaging high-speed train lines, the Paris prosecutor’s office said.

Julien Coupat, 34, was arrested by anti-terrorist police in November 2008 and his lengthy detention without charges being filed had become highly controversial.

His arrest was part of a wider swoop on members of what Interior Minister Michele Alliot-Marie described as an “anarcho-autonomous” movement that had been under surveillance by domestic intelligence services for months beforehand.

Coupat, the last of the 10 suspects arrested in November to remain in custody, has always said he was innocent but he is still under investigation for organised, terrorism-related destruction of property.

Under the terms of his release, he will have to stay in the Paris region and surrender his passport and identity papers.

The failure to secure any convictions after a highly publicised raid by hundreds of police has proved embarrassing to the government, which has been accused of whipping up terrorism fears to justify tough new security measures.

In a written interview with the Le Monde newspaper this week Coupat described his detention as a “petty revenge which is quite understandable given the means that were deployed and the extent of the failure.”

Read an interview with Julien at  http://tarnac9.wordpress.com/2009/05/28/interview-with-julien-coupat/