The son of a Hamas co-founder said that Israeli authorities released his father in the occupied West Bank on Thursday after holding him without trial for more than two years. Hassan Yousef, 71, was "freed near the southern West Bank city of Hebron" and taken to a hospital in Ramallah where he resides, his son Owais Yousef said. Yousef is a senior leader of Hamas in the West Bank, having co-founded the group in the 1980s along with Sheikh Ahmad Yassine and other Palestinian members of the Muslim Brotherhood. Israeli police did not immediately respond to an AFP request for confirmation. Yousef had been held in Israeli administrative detention since October 2023, shortly after the Hamas attack on Israel that sparked the war in Gaza. Israel has increased its use of administrative detention against Palestinians since the war. The system allows it to detain individuals for renewable six-month periods without charge. Israel says the procedure allows authorities to hold suspects and prevent attacks while continuing to gather evidence, but critics and rights groups say the system is abused. Israel has arrested Yousef several times over the years. He was last released in July 2020 from 16 months of administrative detention. A member of the now-defunct Palestinian parliament, Yousef is estranged from his eldest son Mosab Hassan Yousef, who for 10 years spied against his father's movement. From 1997 to 2007, Mosab Hassan Yousef worked for Israel's internal security agency Shin Bet, before relocating to the United States, where he lives under a new identity and wrote the book "Son of Hamas".