Armed police investigating a bomb blast in Exeter have arrested a man in nearby Plymouth.

Eyewitnesses said the arrest took place outside a cafe in Old Town Street in the centre of Plymouth, the home town of bomb suspect Nicky Reilly.

Another man is helping the police with their enquiries in connection with the investigation but was not arrested. Both men are being questioned by officers.

Police said Muslim convert Reilly, 22, tried to set off a "viable" home-made bomb made from sodium hydroxide, paraffin, aluminium foil and nails in the Giraffe family restaurant in Exeter on Thursday.

Reilly had carried three devices from Plymouth to Exeter on an X38 Stagecoach bus packed with 54 passengers.

He received a text message of encouragement moments before leaving home on the failed suicide mission, police sources said.

Officers began searching a home linked to Reilly in King Street, Plymouth, within hours of the blast.

Devon and Cornwall Deputy Chief Constable Tony Melville said Reilly appeared to be a "vulnerable" individual who had been "preyed upon" and "radicalised".

He said: "Our investigations so far indicate that Reilly, who has a history of mental illness, had adopted the Islamic faith.

"We believe that despite his weak and vulnerable state he was preyed upon, radicalised and taken advantage of."

The Muslim convert, who recently changed his name to Mohammed Rasheed, had a screen saver of the Twin Towers in flames from the 9/11 attacks on his home computer, neighbours said.

Sources said counter-terrorist police were aware of Reilly and suspected he had forged links to known Islamic extremists in south-west England.

There were reports that MI5 was also aware of Reilly but he was not the subject of a live investigation.

Reilly was arrested by police at the scene of the explosion, and suffered lacerations to his eye and facial burns after a device exploded.

Other devices found in the vicinity of the restaurant did not explode.

Mr Melville said: "Witnesses described how a male entered a toilet in the restaurant shortly before an explosion was heard."

Police said Reilly travelled by bus to Exeter from Plymouth, and have released his photograph because they wanted anyone who saw him, or could help track his movements over recent weeks, to contact them.

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