The deadly air strike was Israel's second against a Salafi Islamist militant this week. Militants identified him as Momen Abu Daf, chief of the Army of Islam, among a loose network of Palestinian groups which profess allegiance to al Qaeda and have been reinforced by volunteers who slip in from the Sinai.

Gaza's Islamist Hamas rulers, who have sometimes reined in more radical groups, are seeking an accommodation with secular Palestinian rivals and with an Egypt struggling for order after the fall of U.S.-allied President Hosni Mubarak in February.

Abu Daf died when a missile hit Gaza City's Zeitoun district, the Hamas administration's Health Ministry said. Five other Palestinians were wounded and one of them needed hospital treatment.

The Israeli military said its aircraft "targeted a terrorist squad that was identified moments before firing rockets at Israel from the northern Gaza Strip."

Abu Daf, a military statement said, had "orchestrated and executed numerous and varied terror attacks" and "was actively involved in the preparations of the attempted terror attack on the Israel-Egypt border that was thwarted this week."

EYES ON EGYPT

That appeared to refer to Israel's killing on Tuesday of another Salafi fighter, Abdallah Telbani, who the military said had been plotting strikes in which gunmen would circumvent the fortified Gaza border by attacking south Israel from the Sinai.

Israel has been on high alert for such raids since losing eight of its citizens to armed infiltrators on Egypt's porous frontier in August. Israeli troops repelling those gunmen killed five Egyptian border guards, fraying strategic ties with Cairo.

"We shoot when we're being shot at," one Israeli security official said after Friday's air strike in Gaza. "It's clear that Hamas does not have an interest in fanning the flames at this time, but it's not dousing them either."

Sami Abu Zuhri, a Hamas spokesman, responded: "Our people have the right to defend themselves, and the problem is the (Israeli) occupation which targets the Palestinian resistance."

Though Hamas echoes Salafi calls for Israel's ultimate destruction, its ambitions are framed within Palestinian nationalism, not al Qaeda-style global jihad, and include a possible ceasefire with the militarily superior Jewish state which, with Egyptian help, has tried to isolate Gaza.

Hamas took over the coastal strip in a 2007 civil war against Palestinian President Mahmoud Abbas's Fatah faction, which holds sway in the Israeli-occupied West Bank.

Hamas chief Khaled Meshaal and Abbas held rapprochement talks in Cairo last week against a backdrop of political upheaval across the Arab world, including Syria, where Meshaal retains a headquarters that diplomats say Hamas has scaled back.

One official said Meshaal told Abbas he was "in favor of peaceful resistance and a truce in Gaza and the West Bank at this stage," though Hamas would not meet Israel's core demand for recognition.

Two short-range rockets were launched from Gaza into Israel on Thursday and five on Wednesday, the Israeli military said. There were no casualties. The Popular Resistance Committees, an armed Palestinian faction, claimed responsibility.