Nicky Reilly, 22, suffered eye and facial injuries in the Thursday lunchtime blast in Exeter, Devon and is in the city's Royal Devon and Exeter Hospital.

Reilly, from King Street, Plymouth, who is under police guard, was arrested at the scene of the blast at the Giraffe restaurant. He can be held for 28 days following his arrest under the Terrorism Act.

Formal questioning by police will begin when he is released from hospital.

It is understood that Reilly had an operation which was believed to have involved skin grafts.

Police are still questioning two men seized by armed police outside a cafe in Plymouth, Devon on Friday lunchtime.

One of the men was arrested when 10 armed officers descended on the cafe, and another was detained to help with their inquiries.

The device which partially exploded in the Exeter restaurant was made from sodium hydroxide and paraffin and packed with nails and was designed to detonate when it was shaken.

Reilly was seen to emerge from the Giraffe cafe "covered in blood" and two other devices were later found nearby. He had received a text message of encouragement before he left on the failed mission, sources revealed.

Reilly carried the explosives on a bus which travelled from Plymouth to Exeter with over 50 people on board. The Giraffe restaurant is around 100 yards from Exeter's bus depot.