JERUSALEM -- Prime Minister Ariel Sharon pledged Sunday to escalate a broad Israeli offensive in northern Gaza, saying troops will remain until Palestinian rocket attacks are halted. Israeli officials said the offensive -- in which 58 Palestinians and three Israelis have been killed -- will help clear the way for an Israeli withdrawal.
Israel poured 2,000 troops into northern Gaza after a Palestinian rocket attack on Wednesday killed two preschoolers in the Israeli town of Sderot.
In new bloodshed Sunday, at least seven Palestinians, including a 13-year-old boy, were killed, while a second 13-year-old boy died of wounds sustained earlier.
The fighting, concentrated in Jebaliya refugee camp, has caused heavy damage. Palestinians say Israeli forces have destroyed homes, torn up roads and left a kindergarten in rubble.
The Israeli air force also fired two missiles early Monday at a group of Palestinian militants in Gaza City, wounding three people, including a local Hamas commander. The Israeli military had no immediate comment.
Speaking on Israel Radio, Sharon said he was determined to halt rocket fire on towns inside Israel and shelling of Jewish settlements in Gaza.
"The current situation cannot continue," Sharon said. "We have to expand ... the areas of operation in order to get the rocket launchers out of the range of Israeli towns."
Israel is operating in a five-mile strip of northern Gaza, aimed at keeping its cities and towns out of rocket range.
"The forces will have to remain there as long as this danger exists," Sharon told Israel's Army Radio.
The rocket attacks could complicate Sharon's plan to pull all troops and Israeli settlements from Gaza next year. Sharon insisted Sunday that the pullout would take place on schedule.
Hard-line opponents, including members of Sharon's own party, accuse the prime minister of caving in to terrorism and warn that a pullback will only increase further violence.
Against the backdrop of criticism, last week's fatal rocket attack left Sharon with little choice but to act, said Gerald Steinberg, a Middle East expert at Bar-Ilan University. "Not doing anything ... was not an option the government could accept," he said.
Raanan Gissin, a top adviser to Sharon, said the offensive would pave the way for the withdrawal by striking a tough blow against the militants.
"When we leave, it won't be under the threat of fire," Gissin said. "We have seized the initiative."
After an emergency meeting to discuss the crisis, Palestinian legislators issued a statement Sunday implying militants should stop firing rockets at Israel.
"The Palestinian Legislative Council, while asserting our people's right to resist Israel's ugly occupation, calls on all factions to put this resistance in a strategic frame that is consistent with the Palestinian higher interests," the lawmakers said.
U.N. Secretary-General Kofi Annan called on both sides to halt the fighting. He "reminds both sides ... they have a legal obligation to protect all civilians," according to a statement from his spokesman's office.
Over the weekend, Israeli forces hit hard at Palestinian militants in the Jebaliya refugee camp and the nearby towns. The army has labeled its operation "Days of Penitence."
Some 7,000 Hamas supporters marched through Gaza City on Sunday to protest the raid.
Israeli officials said the military had no intention of setting up a long-term presence in northern Gaza, but they gave no time limit for the operation.
"We will continue this operation as long as we need," said Israel's army chief, Lt. Gen. Moshe Yaalon. "The troops are ready to continue, not in terms of days, but weeks."
In Sunday's fighting, four militants were killed in Israeli airstrikes, including two men riding on a donkey cart just after firing a rocket at an Israeli town.
Later Sunday, militants fired two more rockets into southern Israel. The army said the rockets landed in open fields and caused no injuries.
The army said another militant was shot and killed in nearby Beit Hanoun as he planted a bomb with other militants.
Hospital officials said a 13-year-old boy was killed after being shot in the chest in eastern Jebaliya. Relatives said the boy had been playing outside his home. The army had no immediate comment.
In Jebaliya, Israeli soldiers shot and killed Raed Abu Wadi, 36, a deaf and mute man, as he stood on his balcony, hospital officials and witnesses said. The army said the man was armed and had run at soldiers.
Early Sunday, Israeli forces pulled back a few dozen yards from Jebaliya, leaving a swath of destruction. Bulldozers destroyed rows of homes, uprooted orchards and tore up roads. U.N. officials said dozens of people were made homeless.
In the Tel Al-Zatar area northeast of Jebaliya, a kindergarten was reduced to an open-air pile of rubble. Toys, coloring books and posters of Donald Duck and Mickey Mouse were scattered throughout the dust.
Jaber Abu Oukal, head of the kindergarten, said 400 children ages 3-5 attended his preschool.
"Now they have no place to go," he said. "Those kids will remember forever what the occupation did to their place and who destroyed their toys and took the smile from their faces "
The army did not comment on the kindergarten. But Lt. Col. Ofer, an Israeli battalion commander, said troops were doing their best to avoid civilian casualties, but conceded "accidents happen sometimes."
He said gunmen were using groups of stone-throwing children for cover. "That's why we don't wait anymore. When we see a group of children gathering, we fire warning shots to disperse them."
About 15,000 people living in the area of the raid have been without water and electricity for days. Many ill people have been unable to reach hospitals or get their medicine, which health officials normally distribute at the beginning of each month.
Meanwhile, Israel's U.N. ambassador demanded the world body investigate the actions of its top official in Gaza, Peter Hansen.
Ambassador Dan Gillerman made the call after the Israeli army released video taken by an unmanned aircraft flying over Jebaliya that appeared to show militants loading a rocket into a U.N. vehicle.
The United Nations denied the accusation Sunday, saying the footage showed a worker loading a stretcher into an ambulance.
Israel has long accused the United Nations Relief and Works Agency of anti-Israel bias.