DIANE ABBOTT today pulled up the government for breaching “its own stated policy” by keeping more than 500 victims of modern day slavery in immigration-detention centres.

The shadow home secretary accused immigration minister Caroline Nokes of “misleading the House” after a Freedom of Information request revealed 507 trafficked people in detention.

Asking an urgent question in the Commons, Ms Abbott said: “On June 19 this year, the immigration minister provided a written answer on the possible immigration detention of persons who are in fact victims of modern slavery and the written answer read as follows: ‘There is no central record of such persons, the Home Office therefore does not collate or publish the data requested.’

“But we now learn from Freedom of Information requests by the Independent newspaper that is not the case.

“ … Does the minister accept that when she responded to the written question saying that no data was available she was in fact misleading the House?”

Ms Nokes replied by rejecting the claim that she misled MPs and insisted that there is “no central record of those who have received a positive conclusive grounds decision [of being a potential trafficking victim] and are detained under immigration powers.”

She added: “While this information may be obtainable from the live Home Office Case Information Database, the information would be for internal management only.”

Ms Nokes also said that, out of the 507 people, 479 received a positive reasonable grounds decision during detention and that 328 of the 479 were released within two days of the decision. In total, 422 were released within a week.

Of the 57 who were detained for eight days or more following a decision, 81 per cent were foreign national offenders, according to the Home Office.