The family of an activist who died in the custody of the Palestinian Authority’s security forces called on the International Criminal Court on Thursday to investigate, in what they say is the first communication to the court from Palestinians against their leadership.

Nizar Banat, an outspoken critic of President Mahmoud Abbas’s PA, died in June 2021 after security forces arrested him at a house in the West Bank city of Hebron.

An autopsy conducted by a Palestinian rights groups said Banat was struck in the head and body, leading to his “unnatural death” within an hour of his arrest.

In front of the ICC, the activist’s brother, Ghassan Banat, told Reuters he had come to The Hague to hand over the evidence gathered by his family about the incident.

“The International Criminal Court is our last hope to achieve justice for Nizar Banat,” he said, adding his brother was only demanding an end to financial and political corruption in the Palestinian territories.

The PA, which has limited self-rule in the Israeli-occupied West Bank, did not immediately respond to Reuters requests for comment on the case. It has charged 14 low-ranking officers with various offences in connection with Banat’s death. All have pleaded not guilty.

Amnesty International has called the trial “flawed” and said those who gave the orders to arrest Banat must also be held accountable.

Stoke White Lawyers, the firm that filed the communication with the ICC, said in a tweet that the “grotesque” release of the 14 suspects for a nine-day holiday in June was among factors motivating the family.

The ICC has been investigating possible war crimes and crimes against humanity by the Israeli military or Palestinian groups in the Palestinian territories since March 2021.

Banat’s death heightened criticism of the PA under Abbas, whose popularity has plummeted since he assumed office in 2005, opinion polls show. The incident sparked days of protests in the West Bank that were violently suppressed by Palestinian forces.