The 12 foreign terrorist suspects currently held in top security prisons are to be freed, Charles Clarke will announce today.

The home secretary will say that the dozen men held without trial in Belmarsh and Woodhill jails are to be released and kept under house arrest until they can be deported to their home countries.

The development follows the arrival in London yesterday of four British men who had been held at Guantanamo Bay.

They were immediately arrested and taken to police stations in central London.

Gareth Peirce, the lawyer for one of the men, said: "They are very marked by three years of ill-treatment and torture."

Clarke will tell MPs he had to release the detainees after a law lords’ ruling that indefinitely detaining the men was against the Human Rights Act.

Meanwhile, muslims have been warned by the director of public prosecutions that new laws designed to combat religious hatred would not stop people from being rude about Islam.

Ken Macdonald told MPs on the home affairs select committee that he wanted to play down Muslim expectations.

People will remain "perfectly free to be rude or offensive" about Islam or any other other religion because of the right of free speech, Macdonald said.

He added: "It is very important people understand what the law will achieve. It will stop the grossest form of conduct but it will not stop people being rude about Islam."