A suicide bomber has killed at least 19 people at a restaurant in the Israeli coastal city of Haifa. At least 50 people were injured in the blast.

A female suicide bomber walked into the center of a crowded restaurant, then detonated an explosive charge strapped to her body. A number of children were among the dead and injured.

A police official told Israeli media they were still investigating reports that the bomber had shot the security guard at the entrance to the restaurant, before the bomb was set off. Damage was said to be extensive to Maxim's, a restaurant located at the southern edge of the city, on the beachfront.

The blast blew out windows and did extensive damage to walls and columns throughout the restaurant.

Palestinian chief negotiator Saeb Erekat condemned the attack, and appealed to the quartet of international Mideast mediators - the United States, the European Union, Russia and the United Nations - "to exert every possible effort in order to ensure de-escalation."

Prime Minister Ariel Sharon convened a meeting of senior political and defense officials shortly after the attack. An official in the prime minister's office said Israel demands that the Palestinian Authority take immediate steps against militant groups. David Baker said the bombing shows the Palestinian Authority continues to refuse to take even minimal steps against the terrorist infrastructure.

Israeli media quoted security sources as saying Israel would react harshly to the attack. Israeli security forces have been on high alert in advance of the Yom Kippur holiday, which begins at sundown on Sunday.

Entry to Israel from the Palestinian areas has been closed as a precaution. Such measures are generally taken during Jewish holidays, because of increased concerns about attacks by Palestinian militants during such periods. Saturday's attack was the first suicide bombing since 15 people were killed in early September, near an army base outside Tel Aviv, and at a Jerusalem coffee shop.

After those bombings, Israel threatened to "remove" Yasser Arafat, but did not say when it would act, or what action it would take against the Palestinian leader.

On Saturday, a member of Mr. Sharon's Cabinet, Health Minister Danny Naveh, said Israel should seize this opportunity to get rid of Mr. Arafat.