Israeli security forces have arrested 13 Palestinians and an Israeli Bedouin, believed to be behind the bombing of a bus in Bat Yam, south of Tel Aviv, on December 22.

After gag order was lifted yesterday, it emerged that among those arrested was the man accused of planting the bomb, 20-year-old Palestinian Sami Harimi.

Harimi was arrested in Bethlehem on December 26, and is believed to have confessed to his role in the attack.

Mr Harimi reportedly boarded the bus, and put the explosive, concealed in a bag, in the middle of the vehicle, and got off. He later called a mobile phone attached to the bomb, detonating it.

But thanks to a concerned passenger who spotted the bag, the bus was evacuated and no one was injured in the blast.

Following the attack, Israeli security forces made arrests in the West Bank city of Bethlehem, and detained several members of the Islamic Jihad militant group.

Two of the central suspects are believed to be former prisoners, detained in Israel.

The investigation is still under way and the Shin Bet is expected to make more arrests.