Labour covered up the UK's burgeoning immigration crisis while they were in power, according to secret reports revealed last night.
Documents on Bulgarian and Romanian immigrants, commissioned at a cost of £165,000 to the taxpayer, were never published.
It was claimed that Labour was worried that a damaging row would erupt over the five dossiers before last year's General Election.
Among the hidden details was the revelation that a quarter of migrants arriving from Bulgaria and Romania had low education levels, many had four or more children and were more likely to claim unemployment benefits than other immigrants.
Tory ministers said this"disturbing cover-up" made a mockery of promises made by Gordon Brown and Tony Blair on migration.
Both former Prime Ministers insisted, while in power, that only people from Bulgaria and Romania who brought skills and added value to the UK would be allowed in after they joined the EU in 2007. The Tories are now promising to publish the reports within days.
They also include a predicted population explosion of four million in the 10 years to 2018. The reports also said that unemployment was worse among immigrants and one in three people living in London was born outside the UK.
It was also revealed that net immigration rocketed from 9,200 a year in 1992-1995 to 178,300 by 2004-2007.
Tory MP Philip Davies said last night: "Labour got it wrong then and Labour got it wrong now. This only goes to show what a mess they were in."
Local Government Minister Grant Shapps said: "This is another disturbing cover-up by a Labour Party that failed on immigration and then tried to bury the truth.
This Government is bringing immigration under control to restore public confidence in the system."
The secret reports come as an embarrassing blow to Labour during their party conference in Liverpool this week and shines the spotlight on the party's failings on immigration.
Until 2008, the Labour government effectively operated an"open door" policy where the number of visas, work permits and extended residencies granted ballooned.
Gordon Brown eventually introduced a"points based" system designed to make it harder for non-skilled people to come to Britain from outside the European Union.
Labour leader Ed Miliband yesterday admitted his party's failings on immigration during an interview on BBC1's Andrew Marr show.
He said: "I think we did allow the entry of Poland into the free movement of labour too quickly, and that clearly had effects on people up and down the country, and we've clearly got to learn those lessons for the future when it comes to future accession."
He also admitted: "I think it's very hard to reverse free movement of labour in Europe - British people working abroad benefit from that - but we obviously have to learn lessons from that.
If you have a more open economy in Europe, you've got to put in the right protection for people, for workers. I don't think we did quite enough of that, in ensuring, for example, agency workers got proper protection, so that when people came in from abroad, they weren't used to undercut British workers."