GAZA CITY, Gaza Strip -- Several thousand Palestinians, defying the urging of Hamas to remain in their homes, fled areas in northern Gaza early Sunday after Israel warned them through fliers and phone calls of major attacks to come.
Israel and Hamas seemed to signal little public interest in international appeals for a cease-fire as they continued their barrages. More than 130 rockets were fired out of Gaza into Israel on Sunday, with 22 intercepted, the Israeli army said, while Palestinians expressed anger over the previous day's Israeli strikes on a center for people with disabilities and on a home in an attack that killed 17 members of one extended family.
Early today, Israel also exchanged volleys with Lebanon, to the north, shelling it in response to a cross-border rocket attack, one of a string in recent days, Reuters reported. There was no word on damage or casualties.
Israeli warplanes hammered the vacated Beit Lahiya area Sunday afternoon and evening, hitting alleged launch sites and homes of members of extremist groups such as Hamas and Islamic Jihad. The assault was carried out mostly by air, but the Israeli navy also reportedly fired shells from the sea.
And in the first report of Israeli boots on the ground in Gaza, military officials confirmed a lightning raid overnight Saturday by naval commandos who crossed the border to take out a site believed to be the source of large volleys of rockets launched at cities in southern and central Israel.
The commandos went in under aerial and naval cover and reportedly killed three Palestinian militants in a shootout. Four commandos were lightly wounded, the military said.
The Egyptian government said it would open its crossing into Gaza for U.S. citizens to leave the enclave today. A group of Egyptian political parties called on the government in Cairo to open the crossing indefinitely to help Gazans who have relied on it for supplies to get through. The transit point has been closed since last summer, after the installation of a government in Cairo hostile to Hamas.
Israel opened its Gaza checkpoint for foreign nationals to exit the strip Sunday.
Late Sunday, a rocket was fired into Israel from Syria, but caused little or no damage. Israeli forces fired artillery in response, the military said.
Those fleeing northern Gaza traveled in vehicles, in donkey carts and on foot. Some waving white flags, residents of areas around Beit Lahiya ventured south to seek shelter in United Nations-run schools.
Rafik Said al-Sultan, 44, walked two hours to a school here with his extended family.
"We left because of the terrifying bombing in the night and because of the fliers that warned that any moving body after noon will be struck," he said.
The leaflets warned residents in the north to evacuate before what Israel's military spokesman described as a "short and temporary" campaign against rocket launchers there. Hamas, which controls Gaza, asked residents to stay in their homes and ignore "Israeli propaganda," but many fled anyway.
Mr. Sultan looked over at the young woman next to him and said: "I don't need another tragedy. This is the fiancee of my son." Three days ago, the son, Odai, 21, was killed in an Israeli rocket strike on the taxi he was driving. Mr. Sultan said that he had no idea why it had been attacked, and that it must have been the wrong car. Isra Abbas, the fiancee, 17, was to marry Odai in September.
"The 1948 Nakba is now happening every four years," she said angrily, referring to the Palestinian exodus, known as "the catastrophe," during the Arab-Israeli war.
"We pray to God there will be a truce, for our children and ourselves," Mr. Sultan said, looking around the crowded classroom. "We can't live here. There are no beds and few bathrooms, and men and women are here together."
Down the hall, his nephew Muhammad al-Sultan, 26, had come with his wife and two young daughters on a donkey cart early in the morning after air attacks on his farmland. He conceded that many rockets were fired toward Israel from the area around Beit Lahiya.
"Many rockets go from there," he said.
According to Christopher Gunness, the spokesman for the U.N. Relief and Works Agency, or UNRWA, which deals with the refugees and operates the school, about 17,000 displaced people were already sheltering in 20 UNRWA buildings.
For Israel, poised between international appeals for a cease-fire and a decision on whether to send ground forces into Gaza, the goal now is to ensure a longer lull in Gazan rocket fire, which badly wounded a 16-year-old Sunday in Ashkelon. That can be achieved only by seriously degrading Hamas' fighting capabilities, whether by military means or through diplomacy, Israeli officials say. Part of the strategy, they say, is to cause "pain" to Hamas and its leaders, whose houses -- even those without weapons stores -- Israel is bombing here.
The campaign's death toll among Palestinians was 158, more than half of them noncombatants, and more than 1,100 people have been hurt, the Health Ministry said.
Los Angeles Times contributed.