Former Labour minister Michael Meacher told the Commons today that thousands of sick or disabled people have died after being assessed to find out whether they were fit to work.
He accused contractor Atos of "ruthlessly" forcing the sick and disabled into work.
He said 1,300 people had died after being placed in the "work-related activity group" - those currently too ill to be in a job but expected to take steps towards employment.
Some 2,200 died before the assessment process was completed and 7,100 died after being placed in the group for those entitled to unconditional support as they are too ill or disabled to work.
Mr Meacher said: "Such a mechanistic system has little or no regard to the complexity of the needs of severely disabled or sick persons, the British Medical Association and others have condemned it as not fit for purpose."
Tory Jeremy Lefroy said the government should put Atos in the "last-chance saloon."
Labour former minister Kevan Jones accused the government of having blood on its hands as a result of reported suicides of claimants who were found fit to work by Atos.