The "Israeli enemy raid on Ghobeiri in Beirut's southern suburbs killed six people and injured 15," Lebanon's health ministry said in a statement.

Rescuers had earlier reported three dead in the strike.

"An Israeli strike targeted two floors in a residential building in the Ghobeiri area," a Lebanese security source earlier told AFP, requesting anonymity as he was not authorised to discuss sensitive matters.

The Israeli military said it had "conducted a targeted strike in Beirut" but did not immediately give further details.

An AFP photographer at the site of the strike said it had destroyed two floors of a building located in a densely-packed residential area, also damaging dozens of nearby cars and motorbikes.

A crane was brought in to evacuate residents stranded in their apartments in nearby damaged buildings, the photographer said, with other cranes moving vehicles and removing rubble.

Hezbollah security cordoned off the site of the strike while rescuers looked for survivors amid the rubble of damaged buildings, water tanks and torn electric wires.

On Monday, Israel said it had launched a "targeted strike" on Beirut.

Hezbollah said Ali Karake, its third-in-command, was alive and had moved to safety after a source close to the group told AFP the strike had targeted him.

Hezbollah and its arch-foe Israel have been exchanging near-daily cross-border fire since the Israeli war on Gaza started.

But on Monday, Israel launched devastating strikes across Lebanon's south and east, killing 558 people including 50 children -- the deadliest single-day toll since Hezbollah and Israel last went to war in 2006.

The attacks came after coordinated explosions of communication devices killed 39 people and wounded thousands on Tuesday and Wednesday last week.

Those were followed by a deadly strike on Friday on south Beirut, with leading Hezbollah commander Ibrahim Aqil among the dead.