Israel on Thursday freed a senior leader of Hamas in the West Bank after imprisoning him without trial for 16 months, his son said.
Hassan Yousef, a co-founder of the Palestinian Islamist group, was arrested on April 2 last year at his Ramallah home.
"My father was released from the Israeli prison in Ofer, he is now at home and is in good health," his son Owais Youssef told AFP.
Following his arrest, Yousef, who is considered a top spiritual leader in the terrorist faction, was handed a six-month detention order that was extended for another six months and then for a further four, his son told AFP.
The 65-year-old, who has been arrested multiple times, had been released from a previous 10-month term of imprisonment in October 2018.
Israel's administrative detention system allows the internment of prisoners for renewable periods of up to six months each, without bringing charges.
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.
Around 350 Palestinians were being held under administrative detention orders at the end of May, the latest data currently available, according to Israeli human rights organization B'Tselem.
The group said the evidence against detainees was not disclosed.
A member of the now-defunct Palestinian parliament, Hassan 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 the Shin Bet internal security agency, before relocating to the United States, where he lives under a new identity.