Free speech campaigners have warned extremist Muslims have been 'given the green light to take the law into their own hands' after a knife-wielding attacker was spared jail for charging at a protester who was burning the Koran.

Activist Hamit Coskun, 51, shouted 'f*** Islam', 'Islam is religion of terrorism' and 'Koran is burning', as he held a flaming Islamic text aloft outside the Turkish consulate during a protest in Knightsbridge on February 13.

Moussa Kadri, 59, then came out of a residential building and told Mr Coskun 'I'm going to kill you', before returning and slashing at him with a bread knife. Kadri later told police that he was protecting his religion, prosecutors said.

Protester Coskun was found guilty of a public order offence motivated by 'hostility towards members of a religious group, namely followers of Islam', in June - but his attacker, Kadri, was yesterday spared jail.

The case has been at the centre of a furious free speech row, with MPs warning: 'We now have a blasphemy law in this country.'