Two former detainees at an immigration centre have won the first stage of a High Court bid for a public inquiry into alleged "widespread" abuse.
The two men were held at Brook House, near Gatwick Airport, run by G4S.
Following a BBC Panorama programme in September featuring undercover footage showing alleged assaults and abuse, 10 members of staff were suspended.
The immigration minister, Caroline Noakes, has described the allegations as "appalling".
Lawyers for the two men, referred to as MA and BB, told the court on Tuesday a full, independent and public inquiry was needed to address issues of "very grave concern".
Stephanie Harrison, representing MA, said he was a young man whose mental health "deteriorated progressively" while he was in detention.
'Change of culture'
She said he was "subjected to intentional assaults, humiliation and degradation by officers" and on one occasion an officer threatened to "put him to sleep" while digging his fingers into his neck.
"He resorted to self-harm by food refusal and wounding himself and to multiple attempts at suicide by hanging or strangling," she said.
BB's lawyer, Nick Armstrong, said: "What is striking about the Panorama programme is not just what happened, but how widespread it appears to have been, and the period over which the abuses were committed.
"Perhaps even more striking, however, is the complete failure of any safeguarding mechanism to pick up what was happening."
The home secretary's lawyer, Lisa Giovannetti, said: "The immigration minister has said that she was appalled by the Panorama footage, and is determined that lessons are learned and there is a change of culture."
Mr Justice Holman gave both men permission for a judicial review of the home secretary's decision not to order a public inquiry.
No date has been set for the judicial review hearing.