Israeli security forces found an M16 rifle in a home in the central West Bank village of Wadi Siman early Friday.
The firearm’s owner was arrested, the IDF said.
Israeli security agencies have been cracking down on firearms smuggling in the West Bank over the past year, as well as on workshops in Palestinian cities used to manufacture improvised Carlo-style rifles.
In a separate overnight raid in the West Bank, security forces detained a Palestinian man suspected of taking part in violent protests, according to a statement from the army.
He was arrested in the village of Bayt Fajr, near Bethlehem.