The centre and the house are in Plymouth where officers have searched a number of properties since the attack on Thursday.

They have arrested three people including Nicky Reilly, from Plymouth, a Muslim convert who is understood to have been the only person injured in the explosion.

The blast took place in a busy shopping centre at lunchtime in the Giraffe restaurant.

Devon and Cornwall Police Assistant Chief Constable Bob Spencer said the force would not be releasing any details of the third suspect or where he was arrested.

He said: "We can also confirm the force are searching the Muslim Community Centre.

"This search, as well as another being carried out at a residential address in Plymouth, are both linked to the arrest of the man."

The third man in custody was arrested on Wednesday at 5.30pm.

All three suspects are being held at unknown locations within the Devon and Cornwall force area.

A fourth man is helping officers with their inquiries.