A unilateral Israeli cease-fire a 22-day assault against Hamas militants in the Gaza Strip has gone into effect.
Israel says it is halting military operations in Gaza. Its assault killed nearly 1,200 Palestinians, about half of them civilians.
Israeli Prime Minister Ehud Olmert pledged to stop the offensive early Sunday. But the military warned in a statement that Israeli forces would respond to all violence from Gaza militants.
Israel embarked on its assault to stop nearly daily rocket barrages on its south by militants from Gaza, and to put an end to Hamas arms smuggling. Five of long-range rockets exploded near the southern Israeli city of Beersheba after Olmert spoke but before the cease-fire went onto effect. No one was hurt.
"Olmert says that troops will remain in Gaza - apparently for 10 days," reports CBS News correspondent Robert Berger in Jerusalem. "During that time, Israel and Egypt will work on security arrangements to halt Hamas weapons smuggling to Gaza."
Saying that Israel has achieved its goals in the offensive, government leaders voted to stop the assault during an emergency security meeting Saturday.
"We have achieved our goal," Olmert said. "Hamas has been beaten badly."
Shortly before the Israeli cabinet meeting began, Hamas vowed to keep fighting until Israel pulls its forces out of Gaza and lifts its crippling supply blockade on the territory.
At least one Hamas rocket was fired after the cease-fire announcement, Berger reports.
The Israel offensive has killed nearly 1,200 people, turned the streets and neighborhoods of the Gaza Strip into battlegrounds and dealt a stinging blow to the Islamic militants of Hamas.
In announcing the unilateral cease-fire, Olmert said in a televised address that Israel had achieved its goals, and more: "Hamas was hit hard, in its military arms and in its government institutions. Its leaders are in hiding and many of its men have been killed," Olmert said. But Hamas remained defiant.
Fighting will stop at 2 a.m. local time (0000 GMT), but Israel will keep troops on the ground for the time being, Olmert said. If Hamas holds its fire, the military "will weigh pulling out of Gaza at a time that befits us." If not, Olmert said, Israel "will continue to act to defend our residents."
Olmert addressed worldwide concern about the suffering caused to civilians, who Gaza health officials say make up at least half of the dead.
"In the name of the government of Israel I would like to express my sorrow over the harm caused to uninvolved civilians, for the pain we caused them, for the suffering that they and their families felt because of the intolerable situation caused by Hamas," Olmert said.
The continued presence of Israeli troops in Gaza could mean more clashes, as Hamas has repeatedly said it will not respect any cease-fire until Israel pulls out of the territory.
Hamas spokesman Fawzi Barhoum in Gaza said in a televised address on Saturday that a unilateral cease-fire was not enough to end Hamas resistance - joining the hard-line stance taken earlier by Hamas leaders in exile.
"The occupier must halt his fire immediately and withdraw from our land and lift his blockade and open all crossings, and we will not accept any Zionist soldier on our land, regardless of the price," Barhoum said.
Gaza militants launched eight rockets into Israel around the time Olmert announced the cease-fire, the military said. There were no reports of casualties. Five long-range Grad rockets exploded near the city of Beersheba in the hour after Olmert's televised address, Israel Radio reported.
Palestinians reacted with skepticism and called on world leaders attending a summit Sunday in Egypt to put pressure on Israel to withdraw from Gaza immediately.
"We had hoped that the Israeli announcement would be matched by total cessation of hostilities and the immediate withdrawal of Israeli forces from Gaza," said Saeb Erekat, a top aide to moderate Palestinian president Mahmoud Abbas, a Hamas rival. "I am afraid that the presence of the Israeli forces in Gaza means that the cease fire will not stand and will be fragile."
In Washington, Secretary of State Condoleezza Rice welcomed the unilateral cease-fire and urged both sides to end attacks immediately. In a statement, she also expressed concern for the suffering of innocent Palestinian civilians in Gaza and called for immediate efforts to assist them.
Israel began the offensive on Dec. 27 in response to eight years of bombardments on Israeli towns.
Nearly 1,200 Palestinians have been killed in the three weeks of violence, according to Palestinian and U.N. officials. Thirteen Israelis have been killed.
Even as Israel's 12-member Security Cabinet met to vote on the cease-fire, Israel kept bombarding Gaza. Earlier Saturday, in the northern town of Beit Lahiya, Israeli shells struck a U.N. school where 1,600 people sought shelter. One shell scored a direct hit on the top floor of the 3-story building, killing two boys, U.N. officials said
Egyptian President Hosni Mubarak and U.N. chief Ban Ki-moon both demanded on Saturday an immediate end to the Israeli assault and pullout of all troops.
A summit aimed at giving international backing to the cease-fire is set for Egypt on Sunday. It is to be attended by the leaders of Germany, France, Spain, Britain, Italy, Turkey and the Czech Republic - which holds the rotating EU presidency - as well as Abbas, Mubarak and U.N. chief Ban.
It was not immediately clear whether Israel would send a representative, and Hamas has not been invited.
Israel's key demand is for guarantees that Hamas halt the smuggling of rockets, explosives and other weapons through tunnels under the 8-mile-(15 kilometer-)long Egypt-Gaza border.
Under the deal, Egypt would shut down weapons smuggling routes with international help and discussions on opening Gaza's blockaded border crossings - Hamas' key demand - would take place at a later date.
During its campaign, Israel said it destroyed roughly 60 percent of the hundreds of tunnels.
As it seeks a longer-term solution, Israel signed a deal Friday in Washington in which the United States agreed to commit detection and surveillance equipment, as well as logistical help and training to Israel, Egypt and other nations to monitor Gaza's land and sea borders.
But Egyptian Foreign Minister Ahmed Aboul Gheit said Saturday that his country would not be bound by the agreement. Egypt's cooperation is essential if the smuggling is to be stopped.
As Israel's Security Cabinet met Saturday evening, airstrikes continued. Walls shook and windows trembled in the southern Gaza border town of Rafah as fighter jets soared above head, apparently focusing their missiles on the no man's land with Egypt where many suspected smuggling tunnels lie. But all was quiet after Olmert's announcement for the first time in three weeks, residents said, giving them a chance to sleep.
A total of 13 Palestinians were killed in battles throughout Gaza Saturday, Palestinian medics said.
John Ging, the top U.N. official in Gaza, condemned the attack on Beit Lahiya that killed the two boys - the latest in a series of Israeli shellings that have struck U.N. installations.
"The question that has to be asked is for all those children and all those innocent people who have been killed in this conflict. Were they war crimes? Were they war crimes that resulted in the deaths of the innocents during this conflict? That question has to be answered," he said.
The Israeli army said it was launching a high-level investigation into the shelling, as well as four other attacks that hit civilian targets, including the U.N. headquarters in Gaza. The army investigation also includes the shelling of a hospital, a media center and the home of a well-known doctor.