Israeli troops crossed into Gaza and killed two Palestinian militants who were planting a bomb along the border fence before dawn Friday, the Israeli military said.

Violence has largely abated along the tense frontier since Israel's devastating offensive against Gaza's Hamas rulers early this year, but sporadic border violence and rocket fire have continued.

Soldiers posted along the border spotted the two men planting a bomb near the fence and crossed into Gaza to engage them, the military said. The gunmen were killed in the ensuing firefight.

The military says the men were carrying rifles, grenades and an improvised explosive device. Militants have often used such devices to target Israeli military patrols along the border, planting bombs under cover of darkness and detonating them later by remote control.

Palestinian medics retrieved the bodies of the two men, who were in military uniform, according to Dr. Moaiya Hassanain of the Gaza Health Ministry. He gave their ages as 22 and 28. They belonged to the militant group Islamic Jihad, according to an announcement on the group's Web site. Hours later, militants detonated a bomb near an Israeli patrol jeep in a different section of the fence. The Popular Front for the Liberation of Palestine claimed responsibility in an e-mail sent to reporters.

The military said there were no Israeli casualties in either incident.

Most violent incidents in recent months have been claimed by small militant factions and not by Hamas, which might be trying to avoid provoking further Israeli retaliation.

Gaza is still struggling to rebuild after the offensive Israel launched nearly five months ago in an attempt to halt years of rocket fire at Israeli towns. The three-week offensive claimed some 1,400 lives in Gaza, including more than 900 civilians, according to Palestinian officials and human rights groups.

Israel says the death toll was lower than that and that most of the dead were militants. It blames Hamas for the civilian casualties, saying the militants used schools, mosques and residential areas for cover. Thirteen Israelis were killed during the fighting.

Israel pulled all of its troops out of Gaza after the offensive ended in mid-January. But small forces have occasionally crossed back inside in short incursions to battle militants or defuse bombs along the border fence.

Friday's gunfight took place near one of the border crossings where Israel allows a trickle of humanitarian aid into the territory. Gaza has been blockaded by Israel and Egypt since Hamas seized power there nearly two years ago.

Meanwhile, in the West Bank, two Palestinians were wounded in the weekly protests in the village of Naalin, where Palestinian and international activists regularly protest against the construction of Israel's separation barrier.

The military said some 400 protesters hurled firebombs and rocks and rolled burning tires at Israeli troops who responded with riot dispersal means. Two rioters were wounded in the exchange. Associated Press Television News footage showed one of the protesters being struck in the head by what looked like a gas canister.