The Home Secretary faces legal action over claims that MI5 colluded in the torture of a former civil servant suspected of terrorism, the Home Office said.
Lawyers for Briton Jamil Rahman wrote to Jacqui Smith claiming that she colluded in assault, unlawful arrest, false imprisonment and breaches of human rights legislation.
According to The Guardian newspaper, he says he was tortured over a two-year period in Bangladesh and two MI5 officers turned a blind eye to his treatment.
They would leave the room while he was severely beaten, Rahman claims, and would then return to resume their interrogation.
At one point he says his wife was held in the next room and Bangladeshi officers threatened to rape her.
The Guardian says Rahman's lawyers claim to have evidence, including eyewitness testimony and medical information.
A Home Office spokeswoman said his legal team had written to the Home Secretary and said the Government would respond "in due course".
The latest claims follow accusations by former Guantanamo Bay detainee Binyam Mohamed, who said he was tortured in Pakistan and Morocco with the knowledge of MI5.
And last month Scotland Yard said it was investigating reports that the security services were complicit in the abuse of 29 prisoners, including Britons, abroad.
