Ghislaine Maxwell’s lawyer has claimed the British socialite was physically abused at a federal prison on Brooklyn and punished for making a complaint.

Bobbi Sternheim wrote in a letter to a Manhattan federal judge that the abuse occurred recently at the Metropolitan Detention Centre as Maxwell was undergoing a pat down search in her isolation cell.

The lawyer said Maxwell, the ex-girlfriend of disgraced financier Jeffrey Epstein, asked that a camera be used to capture what was occurring, but a guard “replied ‘no'”.

“When Ms Maxwell recoiled in pain and when she said she would report the mistreatment, she was threatened with disciplinary action,” Ms Sternheim said.

Days later, Maxwell was retaliated against for reporting the abuse when a guard ordered her into a shower to clean, sanitise, and scrub the walls with a broom, the lawyer said.

She added that Maxwell was denied a request the encounter with the guard in the tight space be recorded.

A spokesperson for prosecutors declined to comment and a message seeking comment was sent to the federal Bureau of Prisons.

Maxwell, 59, is awaiting trial on charges that she recruited three teenage girls for Epstein to sexually abuse in the 1990s and committed perjury during 2016 depositions in a civil case.

She has pleaded not guilty ahead of her trial, due to begin in July.

She has been held without bail since July, when she was arrested almost exactly a year after Epstein was arrested to face sex trafficking charges.

Epstein killed himself in a Manhattan jail a month after his arrest.

In late December, a judge rejected a 28.5 million dollar (£21.2 million) bail proposal for Maxwell, saying she was a flight risk and was not forthcoming with authorities about her finances after her arrest.

In Tuesday’s letter, Ms Sternheim repeated assertions made before that Maxwell is being subjected to onerous conditions that include repeated searches and being awakened every 15 minutes by a light flashed into her cell when she sleeps.

The lawyer said the prison is reacting to Epstein’s suicide.

Ms Sternheim said Maxwell has been physically searched approximately 1,400 times in the last seven months and no contraband has ever been found despite hundreds of physical searches of the cell where she lives alone as well as her locker, legal papers, and personal effects.

She said her client is under 24-hour surveillance by up to six guards and approximately 18 cameras, not including a hand-held camera trained on her when she is moved outside the cell.

Meanwhile, harsh treatment that includes food so poorly prepared that it sometimes cannot be eaten has taken a toll, the lawyer said.

“She is withering to a shell of her former self – losing weight, losing hair, and losing her ability to concentrate,” she wrote.

“In addition to the many difficulties impacting her review of electronic discovery materials, the over-management and stress are impacting her stamina and effectiveness in preparing her defence and conferring with counsel.”