JERUSALEM, June 16 (Reuters) - Israel's Supreme Court on Tuesday rejected an appeal to release a prominent Palestinian doctor who has been held without charge since he was captured in Gaza in late 2024.

Hussam Abu Safiya, the director of the Kamal Adwan hospital, is among at least 14 doctors from Gaza who have been detained in Israel without charge for more than a year.

The court based its decision on "confidential materials" that were not shared with Abu Safiya or his lawyer, Naji Abbas, director of the Prisoners and Detainees Department at the Israeli rights organisation Physicians for Human Rights Israel (PHRI), told Reuters on Tuesday.

A spokesperson for the Supreme Court declined to comment.

"The message sent by this decision is unmistakable: a medical professional can be deprived of his liberty indefinitely without being charged and without the authorities presenting evidence against him in open court," Abbas said in a statement.

Abu Safiya's lawyer and human rights groups say the medic has been denied sufficient food and assaulted in prison.

Israel's prison service has denied the allegations.

Abu Safiya appeared by video link at a Supreme Court hearing in Jerusalem last Wednesday, looking noticeably thinner.

For the past 13 days, Abu Safiya has also been held in solitary confinement, PHRI said.

The Israeli military has accused Abu Safiya of being a member of the Palestinian militant group Hamas. It has not provided evidence and Gaza's health ministry and Hamas have denied the allegation.

In 2023, Abu Safiya was among the doctors who refused to leave the dozens of newborn infants they were treating after the Israeli military ordered them to leave.

(Reporting by Pesha Magid; Editing by Kate Mayberry)