“He had been arrested while performing his humanitarian duty during the massacre of medical teams in the Tel Al-Sultan area of Rafah Governorate,” the PRCS said.

The PRCS reported last month that Israeli forces opened fire on the medics, who were driving in ambulances to assist wounded Palestinians at the site of an earlier Israeli attack.

When United Nations and Palestinian officials were able to reach the area a week later, they found a mass grave where bulldozed ambulances and bodies were buried.

Eight PRCS workers were killed along with six Palestinian Civil Defence team members and one UN employee, the PRCS said.

Al-Nassasra, 47, is one of two people who survived the attack.

The other survivor, Munther Abed, said at the time that he had seen al-Nassasra being captured, bound and taken away.

Israel has carried out an intensified campaign of arrests during the war. According to the Palestinian prisoner support network Addameer, at least 9,900 Palestinians are currently being held in Israeli detention facilities, including 400 children

Reporting from the city, Al Jazeera’s Tareq Abu Azzoum said the released detainees reported being tortured in “horrific ways” and were in a bad physical and psychological state