Israeli warplanes struck stronghold of Lebanese Shiite militant group Hezbollah in southern Beirut on Friday morning, the pan-Arab television channel al-Jazeera reported.

Israeli warplanes fired missiles at targets in southern Beirut, including a fuel storage tank at a power station, killing four and wounding 50 others, al-Jazeera said.

Meanwhile, local residents said that at least four huge explosions and anti-aircraft gunfire were heard in southern Beirut.

Friday's bombardment came after Thursday's series of air raids, during which ten bridges, two power stations and the international airport of Beirut were demolished.

Israel pounded Lebanon following a cross-border attack by Hezbollah militants on Wednesday, during which two Israeli soldiers were captured and eight others killed.

Some 47 Lebanese have been killed since Israel began a land, sea and air assault on Lebanon in response to the Wednesday attack.