In the latest Israeli strike, four gunmen from the radical Islamic Jihad group were killed in a car in the northern town of Jabaliya, medics and the army said.

Nine people were killed in Israeli air raids in Gaza late Sunday -- six civilians and two Hamas militants were killed in a strike near the home of Hamas member of parliament Khalil al-Haya, and a civilian was killed in a raid on a metal workshop.

Israel will kill exiled Hamas political supremo Khaled Meshaal "at the first opportunity" and could also target prime minister Ismail Haniya, warned Public Security Minister Avi Dichter, a member of the powerful security cabinet.

Meshaal, who is now based in Syria, survived a Mossad assassination attempt in Jordan in 1997. Haniya escaped an Israeli strike in Gaza in 2004 that killed Hamas's wheelchair-bound founder and spiritual leader, Sheikh Ahmed Yassin.

"He (Meshaal) is a more than legitimate target and I am convinced that at the first opportunity we will rid ourselves of him, despite the difficulty of the task," Dichter told army radio.

Asked whether the Hamas prime minister could also be a target, Dichter said: "If Haniya is part of those who give the orders to carry out attacks, that will make him a legitimate target."

Several other key ministers have made similar comments.

In Damascus, a senior Hamas official shrugged off the warning as "nothing new" and said that the group had taken preventative measures that amounted to "an open battle" with Israel.

"We are used to these threats," Mussa Abu Marzuk told AFP. "It's an Israeli policy that has targeted Palestinian leaders since 1948" when the Jewish state was created.