GAZA CITY, Gaza Strip – A Palestinian bulldozer yesterday demolished the seaside homes of three senior officers who built illegally on public land in Gaza, the start of what the Palestinian government promises will be a relentless campaign against corruption.

Palestinian Arabs, fed up with years of corruption by security officials, hailed the move as an important sign that no one is above the law.

Palestinian leader Mahmoud Abbas was elected, in part, on a pledge to reform the government and security services, where top officials routinely misuse their power for personal gain.

In recent weeks, he has forced top security leaders into retirement and promised to streamline and restructure the security services, which grew increasingly corrupt during the chaos that accompanied 4 1/2 years of fighting with Israel.

“The Palestinian Authority policy is clear. No one is above the law, and we will work until we put an end to the lawlessness in the Palestinian areas,” said Tawfik Abu Khoussa, spokesman for Palestinian Interior Minister Nasser Yousef.

To carry out Mr. Abbas’s mission, one bulldozer guarded by seven jeeps and 30 Palestinian officers entered the Sudania area on the coast of northern Gaza yesterday morning to crush the three homes, which were being built by a major, a lieutenant colonel, and a colonel on public land they illegally seized. The operation encountered no resistance.

Later yesterday, Palestinian police arrested three Hamas militants carrying homemade rockets in their car, the Interior Ministry spokesman said. This came a few minutes after militants fired two rockets at an Israeli town just outside Gaza. Mr. Abbas has spoken out against the rocket attacks. In January, he deployed police to stop them.

A Hamas spokesman said Hamas is committed to a truce declared February 8. Palestinian officials said yesterday’s demolitions – which came after Mr. Abbas ordered the destruction of hundreds of illegal shops, cafes, and kiosks near the beach in Gaza City in January – signaled a wider crackdown on corruption.

“The demolition of the three houses today is the beginning, and any other abuse is going to be resolved the same way,” Abu Khoussa said.

“When my family told me this morning over the phone that the police and bulldozers came to knock down the house of the colonel, I told them they were dreaming. But now I see that the dream became a reality,” said Hassan Abdel Khaleq, a nearby resident. “I hope that all the violators will be punished.”

The demolitions sent an important message to Palestinian Arabs that corruption will no longer be tolerated, said Ghadeer Omari, a Palestinian human rights activist.

“This is a good start. Many officers and many officials abused their authority in the past, and to start with them is going to encourage people to obey law and order,” Mr. Omari said.

Political analyst Hani Masri said that while Mr. Abbas’s move was important, much more must be done to end corruption in the security services, which need “a revolution from inside.”

Also yesterday, the Israeli military lifted a closure banning Palestinians from entering Israel. The closure, which affected about 11,000 Palestinian workers and merchants, was imposed on April 21 before the Jewish holiday of Passover and was to be canceled at the end of the holiday Saturday night.

According to a military statement, it was extended because of “specific information indicating the intention of terrorist organizations to carry out attacks in the heart of Israel.”

Meanwhile, an Israeli soldier and a Palestinian militant wanted in a Tel Aviv suicide bombing were killed yesterday in a shootout that capped a recent rise in violence that has tested a three-month-old truce between Israel and the Palestinians.

Yesterday’s incident began when troops raiding the West Bank village of Saideh cornered two militants, who began shooting, killing one soldier and lightly wounding another. The soldiers returned fire, killing one militant and wounding the other, the army said.

The dead militant was identified as Shafiq Abdul Ghani, 34, from the extremist group Islamic Jihad. Abdul Ghani was arrested by the Palestinian security services as a suspect in a February 25 suicide bombing in a Tel Aviv nightclub that killed five Israelis. He fled a Palestinian prison last month.

The army identified the soldier, the first killed by militants since the truce was declared February 8, as Staff Sergeant Dan Talasnikov, 21.