Secretary of State Condoleezza Rice earlier in the day said she expected a U.N. resolution for a cease-fire within a week. But as she headed to Washington after a visit to Jerusalem derailed by the Qana strike, she struck a more pessimistic tone.

"There's a lot of work to do," she told reporters. "You have to get all the work done, you have to get it done urgently."

The central focus for a peace deal has been the deployment of a U.N.-mandated international force in southern Lebanon to ensure guerrillas do not attack Israel. But details of the force still must be worked out. With talks continuing, the U.N. postponed a Monday gathering meant to sound out contributions to a force.

Hezbollah's allies Syria and Iran quietly entered the diplomacy. Egypt was pressing Syria not to try to stop an international force in the south, diplomats in Cairo said. Iran's foreign minister pulled into Beirut for talks with his French and Lebanese counterparts.

Syrian President Bashar Assad called on his army Monday to increase readiness to cope with "regional challenges." Travelers from Syria have reported that some reservists have been called up for military duty - a sign that Syria is concerned the fighting in Lebanon could spill over.

Thousands of Lebanese took advantage of the lull in airstrikes to make a dash for safety farther north after weeks trapped in homes in the war zone, afraid to move because of intense missile strikes on roads.

Across the south, cars and trucks packed with women and children, mattresses strapped to the roofs and white flags streaming from the windows, made their way to the coast, then turned north. They passed flattened houses, shattered trees and burned-out cars strewn on the roadside.

At one point north of Tyre, vehicles gingerly made their way around a gigantic crater half filled with water into which a car had toppled when a missile struck.

In Qana, grocer Hassan Faraj, who had sworn a day earlier never to leave jumped at the chance to escape. He shuttered his shop and loaded his wife and child into a van to go north into the mountains.

"My mother is very unwell, I must go and see her," he said, explaining his change of mind and insisting he was just dropping off his family to return.

Aid groups were caught off guard by the sudden break and struggled to rush aid to the south.

Outside Marjayoun, a U.N. peacekeepers' convoy carrying food found the bridges across the Litani destroyed. So the trucks drove across the knee-deep waters. Indian peacekeepers assembled a ramp out of stones to get them up the steep opposite bank.

Nearby, the battle raged between guerrillas and soldiers. Warplanes struck around the village of Taibeh to give ground cover after Hezbollah fighters hit a tank with an anti-tank missile. The guerrillas also fired mortars into the nearby Israeli town of Kiryat Shemona, causing no casualties.

Hezbollah announced that five of its fighters were killed in the clashes, bringing the group's acknowledged death toll to 43. Israel says dozens more fighters have died.

Israel carried out two other airstrikes. One killed a Lebanese soldier in his car outside Tyre, prompting Israel to express its regrets, saying it had believed the vehicle was carrying a senior Hezbollah official. The other strike hit the main Lebanon-Syria border crossing for the third day in a row.

Hezbollah also claimed to have hit an Israeli warship off the coast of Tyre with a rocket, the second hit it would have scored on a ship. But Israel denied any of its warships were hit Monday.

The guerrilla group did not shoot a single rocket into Israel as of early evening, a remarkable turnaround for an area that had been hit by dozens of missiles each day during the offensive.

At least 524 people have been killed in Lebanon since the fighting began, according to the Health Ministry. Fifty-one Israelis have died, including 33 soldiers and 18 civilians who died in rocket attacks.