A charity says all failed UK asylum seekers should be medically examined after it uncovered evidence that many are beaten and violently restrained.
The Medical Foundation for the Care of Victims of Torture said 12 out of 14 asylum seekers examined by doctors had suffered "excessive or gratuitous force".
The foundation described the findings, which are contained in the report Harm on Removal that was published this week, as "extremely concerning".
"There may be a systematic problem of abuse rather than a number of isolated incidents," the report claims.
The charity wants the victims and witnesses of alleged assaults to be allowed to remain in the country to pursue legal action.
A Home Office spokesman denied that the report revealed systematic abuse.