GAZA CITY, Gaza Strip (AP) – An explosion Saturday on the outskirts of Gaza City destroyed a black Mercedes, killing four Palestinians and injuring one. Palestinian officials claimed the car came under Israeli tank fire, but the military denied involvement.

Israeli tanks and helicopters were in the general area of the blast in al-Zahra, not far from the Jewish settlement of Netzarim. But the Israeli army said it had not fired at any car and its soldiers were not in the immediate area of the explosion.

Instead, a military source said an army helicopter had fired machine-gun warning shots earlier near the area where Palestinian gunmen were firing at soldiers.

The Palestinian Public Security directorate in Gaza, after first saying the car was destroyed in an Apache helicopter missile strike, issued a statement saying further investigation revealed the damage was caused by a tank shell.

The Popular Resistance Committees, a militant extremist group that includes former members of all Palestinian factions, said three of the four people killed were its members. The fourth, it said, was the motorcycle driver.

The group claimed Israeli forces had planed a bomb in the car and detonated it by remote control from a helicopter in the area.

Israeli military sources, speaking on condition they not be further identified, said they believe the blast was either a “work accident” – the premature explosion of a bomb – or that the car hit a Palestinian-planted explosive device along the road.

Palestinian medical workers collected remains from the twisted shell of the car as blood pooled nearby. An Israeli tank could be seen about 600 yards away.

Ramadan Moner, 29, ran out of the restaurant where he works just 100 yards from the scene.

“I saw flying parts of a car in addition to human body parts,” Moner said. “I rushed to the place. There was a group of people, and we started collecting remains of the body parts and then handed them over to an ambulance driver.”

Palestinian witnesses said that among the victims was the driver of a nearby motorcycle also moving along the Gaza coastal road. It wasn’t clear if the motorcyclist was injured or among the dead.

Ibrahim al-Musder, director of Al-Aqsa Martyrs Hospital in nearby Deir el-Balah, said the remains of four people were brought in along with one injured person.

“The bodies of the people killed arrived in very bad shape, which makes it hard for the moment to identify them,” al-Musder said.

The Hamas militant group claimed in a call to The Associated Press in Gaza that a group of Hamas fighters had ambushed an Israeli undercover unit operating near Netzarim, beginning the day’s clashes.

The Israeli army said it had no information about any ambush. Earlier Saturday, the army said Palestinians had fired two anti-tank missiles and sprayed machine gun fire at Israeli soldiers near Netzarim, but that nobody had been injured.

Later, Palestinian medical sources said a medical worker had been shot in the stomach and wounded.

AP-ES-07-10-04 1309EDT