Israel on Wednesday detained three alleged members of the Lions' Den group in the occupied West Bank, the army said, including the brother of a slain Palestinian fighter.
The arrest of Muhammad Al-Nabulsi and two others in Nablus comes a day after five Palestinians were killed during an Israeli army raid in the city.
"Muhammad Al-Nabulsi was suspected of possessing weapons, manufacturing explosive devices and involvement in the 'Lions' Den' terrorist group," the army said in a statement.
His brother Ibrahim Al-Nabulsi, nicknamed "The Lion of Nablus", was shot dead by Israeli forces in August and has since become a folk hero among Palestinian youth.
The Lions' Den has emerged in recent months amid a sharp rise in raids by Israeli forces in the northern West Bank.
The three arrests on Wednesday follow the killing on Tuesday of Wadih Al-Houh, described by Israel as the head of the Lions' Den, and four other Palestinians in Nablus.
A further 20 Palestinians were wounded in the Israeli raid, the Palestinian health ministry said.
The New Arab is providing live updates from the occupied West Bank.