Three illegal immigrants who have escaped from the Campsfield House detention centre remained on the loose tonight.

Police launched a manhunt after seven detainees were found to be missing from their beds at the centre on the outskirts of Kidlington early today.

Three escapees were recaptured within a mile of the centre and a fourth - who had convictions for assault and theft - was picked up by police in Oxford this afternoon.

The three missing men were not described as dangerous but the public were warned not to approach them.

Inspector Graham Sutherland, who is commanding the police operation, said: "The search continues and anything goes - from out-houses, hedgerows, ditches, the lot.

"Everything is covered, until we're happy they're cleared and we can move on.

"We're keeping an open mind as to whether the men are in the area or have gone further afield but we have extended our search area.

"We would not describe them as dangerous and from the information we have they are low-risk.

"But we don't want the public to approach them and getting into situations they should avoid."

Detention centre staff working for GEO, which runs the centre, raised the alarm at 3.30am, but it is not known exactly when they broke out.

The men fled via the rear of the detention centre and got away over fields towards Begbroke, in what police described as a planned escape.

Police found one man riding a BMX bicycle along the A44 between Begbroke and Woodstock, a second was walking toward Oxford, while the third was found with ankle injuries and is in hospital under police guard.

The fourth man, a Libyan, who has spent time in a British prison for theft and assault, was found at Oxford Botanic Garden, in Rose Lane, at 2pm.

Two of the three missing men are from Palestine and one is from Afghanistan.

None of them has committed crimes in Britain. They are failed asylum seekers who were awaiting deportation.

Police dogs, a helicopter and 22 officers searched the area around Campsfield House and patrolled nearby villages.

Every Thames Valley Police officer who has been issued with new BlackBerry digital assistant devices was sent photos of the wanted men.

Mr Sutherland said that officers were also investigating whether last Saturday's riot at the centre and today's break-out were linked.

He appealed for members of the public who see the wanted men not to approach them and to call the police immediately on 08458 505505.

The Home Office refused to promise it would stop the escapes from Campsfield House immigration centre.

Today's incident was the second break-out in less than a year. Six men out of the 27 who broke out last August are still at large.

There have also been three violent incidents at the centre, in Langford Lane, in the past 16 months.

Kidlington residents demanded that the Home Office - which contracts private firm GEO to run the centre - sort out the security breaches.

But Home Office spokesman Nick Logan said: "We have no update or further comment at present on the Campsfield issue."

Senior Thames Valley Police officers held talks with officials from the Borders and Immigration Agency - part of the Home Office - and managers at Campsfield House about security. The centre holds failed asylum seekers awaiting deportation.

John England, 58, of Begbroke Crescent, near Kidlington, whose garden overlooks Campsfield, said: "I thought last August would be a one-off, but it's happened again. I think all the local residents are very concerned.

"These people need to be contained - it's very worrying. I hope the Home Office can keep them from escaping again."

Kidlington Parish Council clerk Trish Redpath said: "We have very grave concerns about the removal centre and would like reassurance from the Home Office about the safety of our community."

The escape came five days after fires were started during protests that were ended by 200 prison officers and police.

Oxford West and Abingdon MP Dr Evan Harris said he would be seeking answers about this week's incidents.

Dr Harris said: "It's unacceptable for local residents and for the welfare of staff and detainees alike.

"It seems that lessons have not been learned following previous disturbances and it's time for a proper, fully independent investigation.

"There's something wrong with the way the Home Office is operating the system, or the way GEO is running the centre and I will be speaking to Home Office minister Liam Byrne as soon as possible."

The Home Office also refused to say if there would be a security review at Campsfield, which can hold up to 215 people.

GEO declined to comment on yesterday's break-out.