The Government today insisted it had clear strategy to identify and remove people who fail to leave the UK when their visas run out, despite a damning report which revealed that the Home Office has no idea where 150,000 potential migrants are.
John Vine, chief inspector of the UK Border Agency (UKBA), said there is no Home Office plan to find out what proportion of this growing number of visa over-stayers are still in the UK illegally.
Tracking over-stayers down and removing them from the country is not seen as a priority for the agency, Mr Vine added.
But the Immigration Minister Damian Green argued this morning that progress had been made since the criticisms were first levelled at the UK Border Agency.
“We do have a strategy, and indeed we’ve been concentrating on these overstayers this summer,” he said.
“In the course of the last couple of months we’ve removed 1,800 of them, so at the time it was a valid criticism and we have gripped it and dealt with it since then.”
Mr Green said there would always be people who tried hard to prevent their removal, but said many people left on their own accord.
The extent of the problems emerged in an inspection of the Hampshire and Isle of Wight local immigration team at the end of last year.
Mr Vine’s report found that cases involving migrants in the UK, such as students, who had been refused an extension of stay were put in a so-called migration refusal pool and told they must leave within 28 days.
Migrants in the pool who were still in the UK included those who should have left but had not done so, those who had applied for leave in another category, who had outstanding appeals or other legal barriers, or who had left the UK voluntarily by a route not captured by e-borders.
Staff underestimated the scale of the problem by about two-thirds, gauging there were between 400 and 600 cases when there were 1,893 in the area on December 12, Mr Vine said.
While the proportion of cases in the local team's pool remained at about 1.2 per cent of all national cases between October and December, the number nationally increased every week from 153,821 on October 17 to 159,313 on December 12, UKBA figures showed.
An analysis of 44 cases by the inspectors found less than half had left the UK, 20 voluntarily and one as an enforced removal.
Of the remaining 23, the inspectors said the “greatest concern” was that the absconder tracing process was not always followed.
Nine of the absconders had not been added to the police national computer as either “wanted” or with a “locate trace” marker.
Some of the 23 were making further appeals to stay, were serving prison sentences or awaiting travel documents, the report showed.
Mr Vine also raised concerns that the effectiveness of the intelligence used to support arrest visits was not measured to ensure an efficient use of resources.
But he added that his inspection of the local team, which was the first such team to be established when it was formed in 2008, showed it was exceeding its removal targets and asylum decisions were made promptly in most cases.
Mr Green is due to answer questions on immigration policy from the Commons Home Affairs Select Committee next Tuesday.
Committee chairman Keith Vaz said: “I am astonished that the UKBA has no idea where 159,000 individuals, the size of a city like Oxford, have gone since their application was rejected.
“The committee has not been given this information despite asking for the number of migrants who are untraceable.”
Shadow home secretary Yvette Cooper said: “The damning conclusion from the Government's own immigration inspector has concluded that the Government is giving a very low priority to finding and removing people who have been refused permission to stay.”