GAZA CITY, Gaza Strip ? Palestinian gunmen made their way into a heavily fortified Israeli army post in the Gaza Strip under cover of morning fog Thursday and started shooting, killing three Israeli soldiers in a 45-minute firefight.

Two attackers were killed soon afterward, but a third hid near the post for several hours before firing on journalists inspecting the scene, wounding an Israeli newspaper reporter in the leg.

The infiltration came as Israeli forces wrapped up an operation in a nearby Gaza refugee camp amid signs of increasing tensions and violence ahead of Israel’s planned withdrawal from Gaza next year.

The earth-and-concrete outpost guards the isolated settlement of Morag in the southeast corner of Gaza. Taking advantage of heavy fog, Palestinian gunmen slipped unnoticed into the post about 6 a.m. and opened fire, killing an Israeli officer and two soldiers and critically wounding another soldier, the military said.

Soldiers fired back, killing two intruders. The shootout lasted about 45 minutes, said Nissim Bracha, a Morag resident. Two AK-47 assault rifles were found on the two gunmen.

A third Palestinian managed to hide near the base for several hours, waiting until journalists arrived for a briefing from an army commander — standard practice after such an attack.

The Palestinian then opened fire, wounding a reporter for the Yediot Ahronot daily in the thigh. The gunman was killed during the ensuing 30-minute shootout.

In a phone call to The Associated Press, three groups claimed joint responsibility for the attack.

Israeli soldiers tend to injured Israeli journalist Itzik Saban, of the Yediot Ahronot daily newspaper, after he was shot while covering an exchange of fire with a Palestinian gunman in the Jewish settlement of Morag in the southern Gaza Strip.

The caller said the gunmen were from Islamic Jihad, the Popular Resistance Committees — an umbrella group of Palestinian factions — and the Ahmed Abu El-Rish Brigades, a group with ties to Yasser Arafat’s Fatah movement.

One gunman was an 18-year-old high school student who had participated in clashes with soldiers in the past, relatives said.

A spokesman for the Popular Resistance Committees, using the nom de guerre Abu Abir, said the plan was for two gunmen to engage soldiers in a battle while a third planted bombs targeting an Israeli military convoy.