In the shadow of the war raging in Gaza, record numbers of Palestinian detainees are filling Israeli prisons, where they face "systemic abuse" and torture, rights advocates warn, calling for international action, AFP reported.

Members of several Israeli NGOs travelled to Geneva this week to raise concerns before the United Nations about a major "crisis" inside the regime’s prisons.

"We are extremely, extremely concerned," said Tal Steiner, the executive director of the Public Committee Against Torture in Israel (PCATI).

"What we're looking at is a crisis," she said.

She said nine people had allegedly died behind bars since October 7, according to Israeli sources.

And "there are almost 10,000 Palestinians in Israeli custody right now... a 200-percent increase from any normal year".

While the UN and others have long raised concerns about conditions for Palestinian detainees in Israeli prisons, Steiner said the situation had worsened dramatically since war erupted in Gaza.

"During the military onslaught on Gaza, there's been a crisis within Israeli detention facilities and prisons that has been really left ignored," said Miriam Azem of the Adalah Legal Center.