Updated

A Palestinian homicide bomber blew himself up among shoppers outside a mall Monday, killing at least five people and putting pressure on Prime Minister Ariel Sharon for a tough response ahead of a fierce election campaign.

Sharon held an emergency meeting of his security Cabinet to decide how to respond to the attack, which wounded 40 people, while Palestinian leader Mahmoud Abbas threatened his own strong action against those responsible.

An Israeli driver who spotted the bomber carrying a suspicious bag toward the mall alerted police. A mall security guard hustled him away from the entrance and pushed him against a wall, where the bomber detonated his explosives. The guard was among the five people killed, police said.

"If the bomber had gotten in, the result would have been much worse," said Israel's police chief, Moshe Karadi.

The bombing was the fifth since a truce took effect last February.

Islamic Jihad, a militant group that has carried out all five of the attacks, claimed responsibility for Monday's bombing, saying it was retaliation for Israeli killings of the group's leaders.

Israel and the Palestinians are in the middle of election campaigns, and more violence could hurt both Sharon and Abbas, who say they support returning to the internationally backed "road map" peace plan.

The blast shattered windows and pocked the outside of the brown multistory building. Pieces of concrete were ripped off the facade, blood stained the walls and debris littered the sidewalk.

More than a half hour after the bombing, one body lay on the ground, its blackened legs sticking out from under a blanket, while another lay nearby under a sheet. Emergency workers rushed wheeled stretchers with the wounded toward ambulances.

The attack occurred before noon, when a man carrying a black bag crossed the street in front of the Sharon Mall in the seaside city of Netanya. An off-duty security guard waiting at a red light noticed the man and alerted police in the car behind him — in a scene caught on security cameras and broadcast on Israel's Channel Two TV.

"Within a second, I knew he looked suspicious," the driver, Nir Hudra, told The Associated Press.

Policewoman Shoshi Attia got out of her car and approached the man, but he started running, she said.

When he put his left hand in the bag, Attia screamed "Terrorist! Terrorist! Take his hand out of the bag," she told Israeli media from her hospital bed. "Then people started running, crossing the street, running in every direction."

A security guard pushed the bomber away from the crowd waiting to get in, she said.

"I was looking (the bomber) in the eye and he pressed (the button) and blew up. I flew, and all I remember is that I was looking in his eye, I saw his gaze," she said.

The huge explosion, also caught on security cameras, sent smoke billowing into the sky and debris flying and clattering to the ground.

In response, the Defense Ministry decided to resume killing Islamic Jihad leaders in the West Bank and to continue an arrest sweep in the West Bank, security officials said, speaking on condition of anonymity because they were not authorized to discuss the details.

"We decided on a series of steps," Defense Minister Shaul Mofaz told Army Radio, refusing to give details.

Sharon could be pressured to mount a tough response ahead of the election. Sharon left his hard-line Likud Party to form a new centrist party, saying it would give him more freedom to seek a peace deal with the Palestinians.

The Palestinians have parliamentary elections Jan. 25, and violence could harm Abbas' Fatah party, laying bare its ineffectiveness in its race against the Islamic Hamas group.

Israeli Foreign Minister Silvan Shalom said the bombing is "more proof of the ineffectiveness of the Palestinian Authority.

"Israel will act against the terror organizations with all its might and all the means at its disposal. Israel's response will be hard and painful," said Shalom, who is running for the Likud leadership.

Abbas condemned the attack and promised an especially harsh response by his security forces.

"This operation ... against civilians causes the most serious harm to our commitment to the peace process, and the Palestinian Authority will not go easy on whoever is proved to be responsible," said a statement issued by Abbas' office.

Islamic Jihad identified the attacker as Lotfi Abu Saada from Illar, a village north of the West Bank town of Tulkarem. A video released by the group showed the bomber posing with a grenade launcher and assault rifles.

Relatives described Abu Saada, 23, as a primary-school dropout who was illiterate and exploited by his handlers. "My son is a poor soul. He doesn't know anything about this," said his mother, Amina.

Israel said Islamic Jihad's continued attacks make it a legitimate target. Israeli troops killed Luay Saadi, a West Bank leader of the group, on Oct. 24, and arrested another leader, Iyad Abu Rob, last month after a daylong siege in the town of Jenin.

During five years of fighting, Netanya, a coastal city 20 miles north of Tel Aviv, has been a frequent target of attacks due to its proximity to the West Bank.

Monday's attack was the first homicide bombing in Israel since Oct. 26, when a 20-year-old Palestinian blew himself up in the town of Hadera, killing seven Israelis.