Beirut, Lebanon ? Backed by tanks, Israeli troops battled their way to a key Hezbollah stronghold in south Lebanon on Monday, seizing a hilltop in heavy fighting and capturing two guerrillas. The U.S. completed its evacuation of 12,000 Americans and said it would switch to bringing in humanitarian aid.

On the 13th day of Israel’s offensive, its forces moved one step deeper into Lebanon as U.S. Secretary of State Condoleezza Rice made her first diplomatic foray since the conflict began – and immediately met resistance (see story, page 1A).

The tangled knots in the negotiations meant fighting was likely to drag on just as the pace of Hezbollah rockets raining down on Israel shows no signs of letting up despite the aerial bombardment of its positions. Air power alone is proving insufficient to rout the guerrillas, who are tough opponents on the ground as well. Mideast observers say Hezbollah only has to remain standing – not beat Israel – to emerge victorious in Arab eyes.

A day after criticizing Israel for “disproportionate” strikes against civilians, U.N. humanitarian chief Jan Egeland accused Hezbollah of “cowardly blending” among Lebanese civilians.

“Consistently, from the Hezbollah heartland, my message was that Hezbollah must stop this cowardly blending … among women and children,” Egeland said. “I heard they were proud because they lost very few fighters and that it was the civilians bearing the brunt of this. I don’t think anyone should be proud of having many more children and women dead than armed men.”

Israel appeared to be easing bombardment in populated areas and roads in Lebanon that has killed hundreds, displaced as many as 750,000 and dismembered the transportation network. Instead, it appeared to be focusing its firepower on Hezbollah at the front. Beirut saw no strikes all day in apparent deference to Rice’s visit.

Lebanese security officials reported three civilian deaths, without specifying where they occurred. Thirty strikes in and around towns and on roads were reported by security officials and Lebanese media – down from 37 the day before.

The numbers do not include strikes on Hezbollah positions that are not in populated areas. Israel reported 270 strikes on Sunday, suggesting that a large number were in more isolated regions.

Still, Hezbollah was able to launch 80 rockets into northern Israel, wounding 13 people, a rate only slightly lower than in past days.

Israel’s overall death toll stands at 40, with 17 people killed by Hezbollah rockets and 23 soldiers killed in the fighting. Sixty-eight soldiers have been wounded, and 255 civilians injured by rocket fire, officials said.

On the Lebanese side, security officials said 384 people had been killed, including 20 soldiers and 11 Hezbollah guerrillas.

Israeli military officials say several thousand troops are moving in and out of southern Lebanon.

At the front, Israeli ground forces waged a fierce battle Monday with guerrillas dug in at the closest large town to the border, Bint Jbail, known as “the capital of the resistance” for its vehement support of Hezbollah during Israel’s 1982-2000 occupation of the south.

Four Israeli soldiers were killed – two in fighting and two in a helicopter crash – and 20 were wounded, military officials said.