Israel resumed sporadic airstrikes, hitting Hezbollah strongholds and supply lines from one end of Lebanon to the other despite a pledge to suspend such attacks for another day in response to world outrage over the killing of 56 Lebanese in a weekend bombing.

Aid groups had hoped to take advantage of the supposed 48-hour lull in airstrikes to get food and medicine to civilians trapped in the south. But Israel denied access to two U.N. convoys. Others who made the journey described airstrikes close to their convoys, and bodies along the road.

Hezbollah fired just 10 rockets across the border Tuesday, well below an average of about 100 a day since the fighting began 21 days ago, Israel said.

But the ground battles were intense.

At nightfall Tuesday, Israeli troops were fighting Hezbollah at several points along the common border. Reporters and Arab television reported especially heavy fighting and Israeli artillery bombardment at the village of Aita al-Shaab.

The Israeli army said late Tuesday that three Israeli soldiers died and 25 were slightly wounded by small arms fire and anti-tank rockets in Aita al-Shaab.

Israeli Cabinet Minister Haim Ramon said the fighting to date had killed about 300 of Hezbollah's main force of 2,000 fighters, which does not include its less-well trained reserves. "That's a very hard blow," he said.

Hezbollah has said only 46 of its fighters were killed. Four were lost in battles with Israeli ground troops in Adaisse and Taibeh, near the Christian town of Marjayoun, about five miles from the border with Israel, Hezbollah said.

To the east at Kfar Kila, reporters saw at least three airstrikes, and the thud of artillery shells from Israeli ground troops was constant. About 20 shells landed in the hills around Kfar Kila during a 45-minute period.

Israeli jet fighters also struck deep inside Lebanese territory, hitting Hermel, 75 miles north of the Israeli border in the Bekaa Valley. Warplanes fired at least five air-to-surface missiles on the edge of the town, targeting a road linking eastern Lebanon to western regions and the coastline.

Six hours later, warplanes returned to Hermel, hitting a pickup truck loaded with cooking gas tanks, security officials said. The canisters exploded, sending flames shooting up from the vehicle for nearly an hour. The driver was out of the truck and not hurt.

In the west, Israeli warships fired artillery into the villages of Mansouri, Shamaa and Teir Harfan around the port city of Tyre. No casualties were reported.

Another strike at an area near the Syrian border, about six miles north of Hermel, targeted the Qaa-Homs road, one of four official crossing points between Lebanon and Syria. Two of the four border crossings are now closed because of damage, and repeated airstrikes have made the main Beirut-Damascus highway impassable.

Polls in Israel show wall-to-wall support for Israel's fight against Hezbollah, even with Israeli civilians enduring a barrage of rocket fire and the army poised for a sweeping ground offensive that is sure to lead to more casualties.

But the deaths of 56 Lebanese in the devastating weekend strike in Qana focused attention on civilian casualties.

Three more civilians were killed and three seriously wounded when Israeli warplanes hit a house in the southern Lebanese town of Lweizeh, Lebanese security officials said Tuesday.

Also, the Lebanese Red Cross said the bodies of 12 civilians were retrieved from the rubble of buildings destroyed in airstrikes on four villages in southern Lebanon and many more were believed still buried. It was not clear when the victims were killed.

At least 532 Lebanese have been killed, including 461 civilians and 25 Lebanese soldiers and at least 46 Hezbollah guerrillas. The health minister says the toll could be as high as 750, including those still buried in rubble or missing. Fifty-four Israelis have died, 36 soldiers as well as 18 civilians killed in Hezbollah rocket attacks.