Updated

As a tenuous cease-fire took hold in the Gaza Strip on Tuesday, Palestinian Prime Minister Ismail Haniyeh appealed to all Palestinians to prevent a resurgence in the internal violence that killed 36 people in recent days.

Much of Gaza was quiet Tuesday, though a Hamas gunman was killed in the southern Gaza town of Khan Younis — a shooting officials from the Islamic group blamed on militants from rival Fatah.

The relative lull in Gaza violence came just as Israel carried out its first response to a Palestinian suicide bombing, carrying out an airstrike early Tuesday on a tunnel dug by Palestinians near the Gaza-Israel border.

Previous truces between Hamas and Fatah militants in the tense Gaza Strip have quickly collapsed, and it appeared unlikely the two sides would comply with all the terms of the current agreement, such as handing over all those involved in killings and abductions.

In the past, Hamas and Fatah gunmen used lulls to prepare for more fighting.

But Haniyeh called for a total halt to the violence.

"Either we maintain this calm," he said, "or everything collapses again, and then everyone will be held responsible."

Fatah spokesman Maher Mekdad said his group would observe the agreement.

"Despite all the bitterness and sadness that we are feeling, we will work to make it succeed," he said.

The power struggle between Hamas and Fatah that has fueled the fighting remains unresolved. The two sides have been at odds since Hamas defeated Fatah in legislative elections a year ago, dividing the Palestinian government between Hamas and Fatah.

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President Mahmoud Abbas of Fatah, who was elected separately two years ago, has urged Hamas, which faces international isolation because of its anti-Israel ideology, to join Fatah in a more moderate coalition. He hopes a softer platform will help end economic sanctions against the Palestinian Authority and allow him to resume peace talks with Israel.

The truce came as a two-month cease-fire between Israel and the Palestinians in Gaza was badly shaken by a Palestinian suicide bombing. The bomber, a 20-year-old from Gaza, struck the Israeli resort city of Eilat on Sunday, killing three people and himself.

Hamas, which controls the Palestinian parliament and Cabinet, praised the attack as legitimate resistance. Abbas, a relative moderate, condemned it, but said he did not think it would affect "the truce between us and the Israelis in the Gaza Strip."

Israeli leaders hinted that a military response was being considered to the attack.

"We will protect the citizens of Israel and we will protect the tourism centers of Israel," Defense Minister Amir Peretz said Tuesday.

Early Tuesday, the army bombed a tunnel that it said was meant for use by Gaza militants for another attack against Israel. No casualties were reported. In the past, militants have dug such tunnels to attack Israeli army outposts and other targets.

Israeli officials believe the bomber traveled from Gaza into neighboring Egypt, then crossed the lightly guarded desert frontier into Eilat. Peretz promised to step up patrols along Israel's southern border to prevent future infiltrations.

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