An explosion during a parade of the militant Palestinian group Hamas has killed 15 people and wounded 80 others, including children, in the Gaza Strip.

Palestinian President Mahmoud Abbas's Fatah faction blamed Hamas for the casualties for holding a military parade in the densely populated Jebaliya refugee camp.

Witnesses say a truck carrying homemade weapons accidentally exploded. But Hamas blamed Israel, saying a drone flying over the area fired a missile at the vehicle. Israel quickly denied any involvement.

Earlier Friday, an Israeli raid in the West Bank town of Tulkarem turned violent and three Islamic Jihad members were killed.

Islamic Jihad retaliated, firing several rockets into Israel that did not cause casualties or damage.

Palestinian chief negotiator Saeb Erekat condemned the Israeli raid and urged calm on all sides.

Some information for this report provided by AP, AFP and Reuters.