Palestinian militant group Islamic Jihad says a suicide bomber who killed two Palestinians and an Israeli soldier on Thursday was one of its members.
Funerals for the Palestinian victims have been held in the West Bank
The claim for the attack on an army checkpoint close to the West Bank town of Tulkarm was broadcast on loudhailers in the nearby village of Attil.
It said the bomber was Suhaib Ibrahim Ajami, 19, a member of Islamic Jihad's military wing, the al-Quds Brigades.
In November, an Islamic Jihad suicide bomber killed five Israelis in Netanya.
The bomber was also from a village close to Tulkarm, one of the group's strongholds.
Islamic Jihad has never agreed to the informal truce with Israel observed by the main Palestinian militant group Hamas, and is committed to Israel's destruction.
On Thursday, the al-Quds Brigades said it would not "stand by with folded arms" over Israel's shelling of a newly-declared buffer zone in northern Gaza and vowed to retaliate in the "centre of Zion".
The Israeli army has said the bomber was travelling in a minibus taxi to attack the Israeli city of Tel Aviv, but blew himself up when he was ordered out by soldiers at a temporary checkpoint and challenged.
Israel has vowed to crack down on militant groups and followed up the attack by arresting 10 Palestinians allegedly connected to the bomber.