Hezbollah said none of its leaders were killed during the air strike.

Israeli military officials said dozens of aircrafts dropped 23 tons of explosives on the bunker in the Bourj al-Barajneh section of southern Beirut.

Three unusally heavy explosions were heard in the evening from the southern districts of the capital.

An army spokesman said Hezbollah's leader, Sheikh Hassan Nasrallah, may have been hiding in the bunker.

Hezbollah said none of its leaders were killed during the air strike.

A statement from the group said: "Hezbollah denies that any of its leaders or personnel were killed during the latest bombardment... in the southern suburb."

The statement added that the building targeted in the raid was a mosque under construction and not a bunker housing Hezbollah leaders.

Central Beirut bombed

On Wednesday, Israeli jets hit central Beirut for the first time and dozens more people were killed in continuing air attacks across south Lebanon, raising the toll there to about 295 people.

A truck in al-Ashrafiya district in central Beirut was struck by fire from an Israeli warship on Wednesday, the first time that central Beirut city had been hit.

Aljazeera's correspondent, Katia Nasir, reported that air raids had killed more than 55 people and destroyed much in the south during the day.

In al-Srifa, at least 15 houses were completely demolished, the head of al-Srifa town municipality told Aljazeera.

News reports said at least 17 villagers, including several children, were killed and 30 wounded.

Afif Najdi, the mayor, said there had been a "massacre committed in Srifa".

"There are dozens dead and massive destruction. Emergency services are putting out fires [but] they cannot reach the houses to recover bodies," he said.

At least 29 other civilians were killed in air raids on other parts of south and east Lebanon, security sources said.

Hezbollah said one of its fighters was killed in the fighting.

Ahmed Fatfat, the Lebanese acting interior minister, said Israel was trying to destroy Lebanon's infrastructure, not just defeat Hezbollah. "Are they turning it into a second Iraq?" he asked.

Red Cross hit

The International Red Cross told Aljazeera that they could not reach areas in Selaa town because of the destruction and road closures.

In al-Ansariya, a Red Cross centre was hit by an air raid, injuring a medic, Red Cross sources told Aljazeera. 

Israeli tanks at the border

A car in Tyre was hit, injuring seven people, the correspondent said, and in al-Nabatiya, two women and three children were killed in their house.

Another Aljazeera correspondent in Lebanon, Basam al-Qadiri, reported that Israel had struck a house in Maarabun town, near Baalbek, killing five civilians.

Another strike hit al-Nabishit area near Baalbek damaging a two-storey building, killing and injuring people, he added.

Israeli warplanes also struck Luci town in west Bekaa.

A base of the Syrian-backed Popular Front for the Liberation of Palestine in the Bekaa was also hit, the PFLP said. The guerrilla group gave no word on casualties.

Beirut's international airport, which was forced to close last Thursday, was also targeted again. Two missiles struck the runway but no casualties were reported.

"The intensive fighting against the Hezbollah organisation shall continue," Israel's inner cabinet said, adding that it was to get back the soldiers and remove the group's threat.

Hezbollah has arrested more than 20 Lebanese and Palestinians they accuse of spying for Israel.

They are accused of providing Israel with information, including the coordinates of positions in Lebanon that Israel could target for shelling.

Border attacks

Israeli troops crossed the border to attack Hezbollah positions. Hezbollah claims six soldiers have been killed and 14 wounded.

The Israeli army earlier announced that two soldiers had died. 

Military officials said Israeli troops crossed the border in search of tunnels and weapons.

Hezbollah said its fighters destroyed four tanks during the clashes near the border.

Two Israeli-Arab children were killed when a rocket hit a house in the northern Israeli town of Nazareth, a military spokesman said.

The two boys, aged three and seven, were playing outside when four rockets launched landed. Eighteen others were wounded in the attack. 

Hezbollah has fired more than 70 rockets into northern Israel on Wednesday.

Israel said on Wednesday that its air strikes had destroyed "about 50%" of Hezbollah's arsenal.

The conflict has forced about 100,000 Lebanese to flee from their homes and many foreign citizens to evacuate.

Lebanese Prime Minister Fouad Siniora said more than 500,000 people had been displaced and appealed for international help.
   
"I call on you to respond immediately and without reservation to our call for a ceasefire and to provide urgent international humanitarian aid," he said in a televised address.

V
illagers in southern Lebanon said food, water and medical supplies were dwindling after roads and bridges were cut in the south.
   
The United Nations Children's Fund has appealed for $7.3 million to meet the immediate needs of women and children.