The strikes, which destroyed an eight-story building and left a crater in the ground, were the fourth in Beirut in less than a week.

Israeli airstrikes Saturday in central Beirut killed at least 20 people, officials said, as the once-rare attacks on the heart of Lebanon's capital continued without warning while diplomats scrambled to broker a cease-fire.

The escalation comes after a U.S. envoy traveled to the region to pursue a deal to end months of fighting between Israel and Hezbollah.

The envoy, Amos Hochstein, was in Israel and planned to meet with Prime Minister Benjamin Netanyahu, seeking a truce in the country’s war with the militant group Hezbollah.

Israeli airstrikes on Saturday killed at least 11 people and injured dozens in central Beirut, as diplomats scrambled to broker a cease-fire. Lebanon’s civil defence said the death toll was provisional as emergency responders were still digging through the rubble looking for survivors.

Saturday’s attack completely demolished a multi-story building in a densely-populated neighborhood. Israel did not say who the strike’s target was.

The ambassador arrived in Beirut on Tuesday, seeking a ceasefire agreement after the Lebanese government and Hezbollah agreed to a U.S. ceasefire proposal

The strikes at 4 a.m. destroyed an eight-story building in central Beirut and left a crater in the ground. Also on Saturday, a drone strike killed two people and injured three in the southern port city of Tyre, according to the state-run National News Agency.

Israeli airstrikes Saturday in central Beirut killed at least 20 people, officials said, as the once-rare attacks on the heart of Lebanon's capital continued without warning while diplomats scrambled to broker a cease-fire.

Israeli officials have demanded freedom to strike Hezbollah in Lebanon as part of any emerging cease-fire deal between the sides, raising a potential complication as a top U.S. envoy was in the region

Hezbollah chief Naim Qassem said in a televised speech aired on Wednesday that his group had reviewed and given feedback on a U.S.-drafted ceasefire proposal to end fighting with Israel, and that a halt to hostilities was now in Israel's hands.