A Muslim convert with a history of mental illness who was “preyed upon and radicalised” injured himself yesterday after a device he was carrying exploded in a busy shopping centre in Exeter.

Nicky Reilly, 22, received serious facial injuries after the device went off at lunchtime in a family restaurant at the new £230 million Princesshay shopping centre. Another device was defused by bomb disposal teams.

Tony Melville, Devon and Cornwall’s Deputy Chief Constable, said last night that Mr Reilly had been “preyed upon, radicalised and taken advantage of”. Mr Reilly’s neighbours said that he had been brainwashed.

Armed police searched his home in Plymouth and last night were keeping him under guard in hospital while he received treatment for lacerations to his eye and some facial burning.

Diners at the Giraffe chain said that they heard three explosions in the restaurant lavatories. Peter Lacey, 63, and his wife Celia, 60, from Exeter, had just arrived to have lunch. “I heard a noise which sounded like a gunshot. About a second afterwards there was another identical sound and maybe a second later a third.

“The staff tried to get into the toilet but it was locked and they must have called the police. They evacuated us very calmly. I saw a man by an ambulance shortly afterwards with police around him and he had blood on his face and clothing.”

Bomb disposal units found a second device outside the restaurant. Both are believed to have contained canisters of a sodium-based explosive.

Mr Reilly’s neighbours described him as “naive and easily lead”.

Daniel Turner, 20, said: ”He is mentally ill and he probably has the mental age of a ten-year-old.

“He changed his name to Mohammed Rasheed about a year ago at a registry office. He was brainwashed into becoming a Muslim by local men. He can’t think for himself.

“Nicky is schizophrenic. We call him the BFG, but he obviously met up with the wrong people.”

Mr Melville said that Mr Reilly’s injuries were not life-threatening. “Investigation into Reilly shows he has a history of mental illness and had adopted the Islamic faith.

“We believe that despite his weak and vulnerable state he had been preyed upon and radicalised and taken advantage of.”

He added that Mr Reilly had travelled by bus from Plymouth and Exeter and that the police were taking the “unusual step of releasing his photograph because want anyone who saw him today to contact us”.

Stephen Otter, Chief Constable for Devon and Cornwall, said: “There were two devices, one on the café and one nearby. We do not know precisely how bad it could have been if they had gone off but it would have been quite serious.

“I cannot confirm if it was a nail bomb. We are still examining the devices.

Police are concerned that this may be a new situation in Britain of extremists taking advantage of mentally or physically disabled people.

Earlier this year a suicide bomber in a wheelchair killed an Iraqi general inside a security headquarters in central Iraq. In a separate incident two women initially thought to have been Down's syndrome sufferers, but later identified as simply having received psychiatric treatment, blew themselves up in Baghdad, killing close to 100 people.

During yesterday’s incident more than 100 police officers from all over the region were drafted in to the city centre, a large area of which was cordoned off with shops, offices and restaurants evacuated.

The police asked business premises in the area to hold onto their CCTV footage in case it became useful.

Juliette Joffe, a director of Giraffe, which has 21 restaurants across the country, said: “Nobody in the restaurant has been injured apart from the person who set it off.”

The Princesshay development was officially opened last September. The scheme has been heralded as the biggest single investment in regeneration in the city’s history. It contains a mix of shops, restaurants and apartments.

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