We have got no information to suggest anyone was in there but it is a possibility

Bedfordshire Police spokeswoman

Police say they cannot be sure of the fate of 25 asylum seekers still missing amid fears that some may have perished.

Thursday night's riot ended in a fierce fire at the �100m complex near Bedford.

A total of 40 asylum seekers are thought to have been involved in the breakout at the centre, which housed 385 refugees.

Smouldering site

A Bedfordshire Police spokeswoman said: "We have got no information to suggest anyone was in there but it is a possibility.

"It is unlikely to be the case but until we have had a chance to look around we don't know."

The extreme heat of the smouldering fire hampered search activities on Saturday.

A safety expert from the fire brigade and a senior police officer will visit the site on Sunday.

The police have begun handing back control of the site to the centre's operators Group Four.

The blaze also destroyed all records kept at the centre near Bedford.

Fire fighters damp down at the �100m centre

Inquiries by the Immigration Service, police and Group 4 are under way into the incident, which caused damage costing an estimated �38m to repair.

There were reports detainees stormed the hi-tech control room to destroy equipment and records.

Ed Blissett, an official with the GMB union which represents 170 of the centre's staff, said four terrified female nurses were "besieged" and locked in a room by detainees while the building was burning.

Officers were attacked when an argument erupted in the visitors' centre on Thursday night and had their keys snatched.

Six people, including two police officers, were injured in the riot.

Closure call

Residents have been speaking out since the incident.

Margaret Turner told BBC Radio 4's PM programme: "I'm very concerned that it can't continue to operate as a detention centre in its current state.

"I don't see how they can prevent what happened on Thursday from happening again."

She said that residents had been promised no-one would ever escape from the centre.

Immigration minister Lord Rooker who has inspected the devastation is to examine fire chiefs' concerns that design flaws helped the fire spread rapidly.

Speaking on the same programme he agreed it was extraordinary no water sprinklers had been installed at Yarl's Wood, despite a fire brigade recommendation a year ago.

"This is the easiest country in the European Union in which to work illegally so we are stepping up our system to deal with failed asylum-seekers," he said.

The destruction of half the building leaves Home Secretary David Blunkett's asylum policy in serious trouble as many of the residents will have to be housed elsewhere.

Built last year to house 900 people, Yarl's Wood is Europe's largest immigration centre.

Group Four said 123 have since been transferred to other sites, with 222 remaining in the undamaged area.