LONDON - A British Muslim convert allegedly persuaded online by shadowy Pakistan-based "extremists" into trying to carry out a suicide bomb attack on a busy restaurant was on Friday jailed for a minimum of 18 years. Nicky Reilly, 22, who has Asperger's syndrome and a mental age of 10, was described as the "least cunning" person ever to have been charged with terrorism. He was directed how to build bombs filled with hundreds of nails, which he attempted to detonate at the Giraffe restaurant in Exeter in May. But the devices went off prematurely and he was the only person to sustain injuries. In Oct last year, Reilly, from Plymouth pleaded guilty to attempted murder and preparing an act of terrorism. Sentencing him today to life at the London's Old Bailey Crown Court, Justice Calvert-Smith said: "I am quite satisfied that these offences are so serious that only a life sentence is appropriate. This defendant currently represents a significant risk of serious harm to the public. "The offence of attempted murder is aggravated by the fact that it was long-planned, that it had multiple intended victims and was intended to terrorise the population of this country. It was sheer luck or chance that it did not succeed in its objectives." Reilly had intended to run out into the packed dining area holding three bottles, filled with caustic soda, kerosene, and nails, to his stomach. But he got stuck in the toilet as he prepared the blast, leaving one of the bottles to go off before he could leave the cubicle. The explosion sent dozens of restaurant customers fleeing in panic and the bomber staggered out suffering serious facial injuries. Counter-terrorism officials said that extremists had taken advantage of his low IQ to groom him.