Tanks, bulldozers and armored personnel carriers knocked down a fence and barreled over the Israel-Lebanon border Saturday as Israeli forces stepped up a small-scale ground offensive into southern Lebanon to try to cripple the Hezbollah guerrilla group.

The soldiers battled Hezbollah militants throughout the day, and raided the large Lebanese village of Maroun al-Ras in several waves before seizing control, military officials said. Tens of thousands of Lebanese fleeing north packed into the port of Sidon to escape the fighting.

The growing use of ground forces, 11 days into the fighting, signaled Israeli recognition that its airstrikes alone were not enough to force Hezbollah out of southern Lebanon. But a ground offensive carries greater risks to Israeli forces, which have already lost 18 soldiers in the recent fighting. And it threatens to exacerbate already trying conditions for Lebanese civilians in the area.

Israeli military officials have said they want to push Hezbollah beyond the Litani River, about 20 miles north of the border, with the Lebanese army deploying in the border zone. An Israeli radio station that broadcasts to southern Lebanon warned residents of 13 villages to flee north by Saturday afternoon. The villages form a corridor about four miles wide and 11 miles deep.

A force of about 2,000 troops, backed by tanks and armored vehicles raced past a U.N. outpost and headed into Maroun al-Ras. Gunfire could be heard coming from the village, and artillery batteries in Israel also fired into the area.

"The forces have completed, more or less, their control of the area of the village, Maroun al-Ras, and made lots of hits against terrorists," said Maj. Gen. Benny Gantz, chief of Israel's ground forces. "It was a difficult fight that continued for not a short time."

Dozens of Hezbollah fighters were injured or killed in the battle, Gantz said. Hezbollah said two of its fighters were killed Saturday, bringing the total number of acknowledged Hezbollah fighters killed to eight. Israel accuses the group of vastly underreporting its casualties.

The village was strategically important because it overlooked an area where Hezbollah had command posts, Gantz said. The forces seized a cache of weapons and rockets in a mosque in the village, he added.

After Israel seized Maroun al-Ras, which is believed to be a launching point for the rocket attacks on northern Israel, several small groups of Israeli soldiers in armored personal carriers traveled to and from the village. U.N. peacekeepers and witnesses said the Israeli forces briefly held the nearby village of Marwaheen before pulling back.

The Israeli army said it wanted to completely destroy all Hezbollah infrastructure in an area between a half-mile to two miles from the border, but it had no intention of going deeper into Lebanon than that.

"We really want to knock out Hezbollah in this area," said Capt. Jacob Dallal, an army spokesman. "We want to wipe them out, and we don't intend for them to ever be there again."

A senior Israeli military official confirmed that Israel did not plan to reoccupy southern Lebanon — as it did from 1982 to 2000 to create a buffer zone to protect northern Israel.

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In other recent developments:

Israeli warplanes fired missiles into the southern Lebanese town of Sidon. Witnesses said the Israeli jets fired two missiles that directly hit the four-story Sayyed al-Zahraa compound. The compound, which contains a mosque, a religious library and a seminary, was entirely destroyed but was believed to be empty at the time of the strike, they said. The compound is run by Sheik Afif Naboulsi, a Shiite Muslim cleric close to Iran and the militant Hezbollah group.

Over the past 11 days, Hezbollah has launched nearly 1,000 rockets into Israel. At least 132 rockets landed in Israel on Saturday, wounding 20 people, three seriously, rescue officials said.

The death toll in Lebanon rose to at least 372, Lebanese authorities said. At least 15 Israeli civilians have been killed by Lebanese rockets, and 19 Israeli troops have died so far.

U.N. Secretary-General Kofi Annan said the conflict has created some 700,000 refugees so far, and Israel's destruction of bridges and roads has made access to them difficult. As part of an effort to avert a possible humanitarian crisis, Israel eased its blockade of Lebanon's ports to allow the first shiploads of aid to arrive.

The U.S. is delivering a shipment of "bunker buster" bombs to Israel. Israel is replenishing its stockpile of precision-guided GBU-28 bombs, reports CBS News National Security Correspondent David Martin, and the bombs are part of an arms package that Israel can tap into whenever it needs. The sale of these weapons was approved by Congress in April of 2005. A military statement at the time said, "The proposed sale of this equipment and support will not affect the basic military balance in the region." Israeli officials won't comment on the shipment apart from saying the army has been using precision-guided weapons to minimize harm to civilians, reports CBS News correspondent Charlie D'Agata from Jerusalem.

Israeli warplanes blasted communications and television transmission towers in the central and northern Lebanese mountains, knocking out the Lebanese Broadcasting Corp. Fighter bombers fired missiles at transmission stations in the central and northern Lebanese mountains, leaving antennas burning on the ground.

Ships lined up at Beirut's port as a massive evacuation effort to pull out Americans and other foreigners desperate to flee. The U.S. State Department said that, as of Saturday morning, 7,500 American citizens have been transported out of Lebanon. The State Department estimated that another 1,600 Americans would leave Beirut on Saturday.

U.S. Secretary of State Condoleezza Rice will visit the Middle East on Sunday, her first trip to the region since the crisis erupted, even as she ruled out a quick cease-fire as a "false promise." CBS News chief White House correspondent Jim Axelrod reports that the fact that Rice is not coming to Israel until Sunday is an implied green light to Israel to keep hammering at Hezbollah for at least two more days.

Italy, which has been trying to mediate an end to the fighting, said it would hold a conference Wednesday to work out the basis for a truce agreement.