Israel launched its deepest ground strike into Lebanon yesterday, sending commandos to attack Hezbollah militants at a hospital in the northeastern city of Baalbek, while nearby air raids killed at least 15 civilians.

Israeli warplanes also attacked a Lebanese army base in the southern part of the country, killing three soldiers, a security official said.

Hezbollah guerrillas hit back yesterday, firing a heavy barrage of more than 50 rockets at towns across northern Israel, wounding at least six people, Israeli rescue services said.

As the fighting escalated, Israel sent up to 10,000 armored troops across the border into southern Lebanon on Tuesday, Israeli defense officials said. Thousands more were gathering at staging areas on the Israeli side of the border, ready to join the battles.

The ferocity of the battles in Baalbek and across southern Lebanon, coupled with the determination of the Israelis to keep fighting and the minimal diplomatic progress toward a cease-fire so far, indicated the three-week-old war is likely to escalate further.

In an interview in Jerusalem, Israeli Prime minister Ehud Olmert told reporters that the fighting will stop only once a robust international peacekeeping force is in place in southern Lebanon. But France said it will not participate in a meeting today at the UN that could send troops to help monitor a cease-fire, even though it may join ? and possibly even lead ? such a force later.

In the raid on Baalbek, near the eastern border with Syria, Israeli commandos flew in by helicopter under cover of heavy airstrikes and waged a fierce battle with Hezbollah guerrillas at the hospital. Israel said several guerrillas were captured and taken back to Israel.

The Israeli military said all its soldiers returned to their base without suffering casualties. It refused to identify the guerrillas who were captured, but Israeli radio broadcast the names of three alleged Hezbollah members it said had been seized in the raid.

Hezbollah denied those captured belonged to the guerrilla group.

?Those who were taken prisoner are citizens. It will not be long before the (Israeli) enemy will discover that they are ordinary citizens,? Hezbollah said in a statement broadcast on its Al-Manar television. Lebanese security officials said at least five Lebanese were captured by Israeli troops, but had no immediate information on whether they were Hezbollah fighters.

Financed by Iranian charity

Witnesses said Israeli forces partially destroyed the Dar al-Hikma hospital in Baalbek, where chief Hezbollah spokesman Hussein Rahal said fighting raged for more than one hour. Speaking on condition of anonymity because of the sensitivity of the situation, residents said the Dar al-Hikma hospital is financed by an Iranian charity that is close to Hezbollah and run by people with ties to the group. Witnesses said Israeli warplanes launched more than 10 attacks around the hospital, as well as on hills outside the city. Jets later fired a second round of missiles on residential neighborhoods in eastern and northern Baalbek where Hezbollah?s Shiite supporters live, witnesses said.

One of the air raids struck the village of Al Jamaliyeh, less than a mile from the hospital. A missile hit the house of the village?s mayor, Hussein Jamaleddin, instantly killing his son, brother, and five other relatives. ?Where is the press? Where is the media to see this massacre? Count our dead. Count our body parts,? Jamaleddin told reporters on the telephone, minutes after the missile strike.

A family of seven ? a mother, father and their five children ? were killed in another airstrike on an area near Al Jamaliyeh, witnesses said. A van driver was also killed when another missile struck nearby.

In the attack on the Lebanese army, Israeli jets fired at least one missile on its base in a highland region where Hezbollah is also believed to have offices and bases, said the security official, who spoke on condition of anonymity because he was not authorized to give official statements.

The death of the three soldiers in the attack brings to 28 the number of Lebanese soldiers killed since the start of the Israeli offensive against Hezbollah on July 12.

The Lebanese military has largely stayed out of the conflict, though has said it will fight if Israel launches a wide-scale invasion, and Israeli warplanes have repeatedly attacked soldiers. It was not clear what prompted the airstrike on the army base.

The 10,000 Israeli soldiers sent into Lebanon crossed the border at four different points and progressed at least four miles inside the country. In an incident denied by the Israeli military, Hezbollah said in a statement that it had attacked an Israeli armored unit that crossed into Lebanon yesterday morning, destroying two tanks and leaving their crews dead or wounded.

The Israelis want to keep Hezbollah off the border so their patrols and civilians along the border are not in danger of attacks. the July 12 raid in which guerrillas killed eight soldiers and seized two others. The army also hopes to push Hezbollah far enough north so that most of the guerrillas? rockets cannot reach the Jewish state.