Officers did not pursue the men, who are still missing

The six men escaped from Dover's Western Heights Removal Centre, but officers did not pursue the group because the escape did not constitute a criminal offence.

Kent Police have described the matter as a "grey area".

A Home Office spokesman said all six escapees, whose applications for asylum had already been rejected, were still missing.

There might be a need to give the police some more powers in these circumstances Dover MP Gwyn Prosser

BBC South East Today has been told the men used a saw smuggled into the centre to make their way to the courtyard, where a rope had been thrown over the perimeter wall.

Bags containing clothes and tickets to London for all the group, which included one Algerian, two Russians, two Belarusians and one Moldovan, were apparently left on the other side.

The incident is being investigated by the Prison Service.

Details of the escape, which occurred exactly a week ago at 1930 BST, only emerged on Thursday.

'Not a criminal offence'

The centre houses 350 asylum seekers, some of whom are waiting for permission to stay in the country and others who are awaiting deportation.

Sergeant Ken Chapman, of Kent Police, said: "It's a grey area, but unless they have committed some sort of crime before their arrival at the centre their escape does not constitute a criminal offence."

Labour MP for Dover Gwyn Prosser said: "There might be a need to give the police some more powers in these circumstances.

"But first of all we would want to find out what has actually happened and why the arrangements which are in place and work very well in other parts of the country might not have worked quite so well in Dover."

Tom Macgowan, of the Kent Committee to Defend Asylum Seekers, said the incident showed how afraid the men were to return to their countries of origin.