Israel Strike Against Hezbollah in Lebanon Kills at Least 20

An Israeli airstrike on a residential building in central Beirut killed at least 20 people on Saturday, the Lebanese Health Ministry said, part of an intensifying Israeli military campaign that appears aimed at pressuring Hezbollah into a cease-fire deal.

The strike was an attempt to assassinate a top Hezbollah military commander, Mohammad Haidar, according to three Israeli defense officials who requested anonymity to discuss sensitive military operations. Hezbollah officials on Saturday afternoon said that none of the group’s leaders were at the site of the airstrike, and later in the day, one of the Israeli officials said Mr. Haidar was not killed.

Over the past week, Israeli ground troops made a concerted push deeper into southern Lebanon while Israel intensified its bombardment of the Dahiya, a cluster of neighborhoods on the southern outskirts of Beirut that are effectively governed by Hezbollah.

The death toll in the latest strike was expected to rise, and at least 66 people were injured, according to the Health Ministry. The strike came just after 4 a.m., jolting Beirut residents awake with thundering explosions that left much of the city enveloped in acrid smoke. It was the third strike this week in central Beirut, an area that had largely been spared since the war between Hezbollah and Israel escalated.

Lebanon’s health minister, Firass Abiad, said the airstrike hit a multistory building that was believed to house at least 35 people in the Basta neighborhood of Beirut, an area that is home to both Sunni and Shiite Muslims and close to several Western embassies. Hezbollah is a Shiite militant group and Shiite communities in southern and eastern Lebanon have borne the brunt of Israeli attacks over the past few months.

The war in Lebanon has killed more than 3,500 people and forced almost a quarter of the population to flee their homes. Some Shiites who fled the Dahiya have taken refuge in Basta, according to residents of the area.

“There was no prior warning,” Mr. Abiad said of the Basta strike in a phone interview. “It appears there are still bodies under the rubble.”

A crowd of onlookers and rescue workers gathered outside the blast site. Among them were Iman Ismael, a refugee from Syria, and her 10-year-old son, who were waiting for news about four relatives who had lived in the destroyed building.

“They are still missing,” she said. “God, please let them survive.”

The building was just three doors down from another building that Israel bombed last month in an attempt to kill another senior Hezbollah official. Zainab Rummu, 54, said the strike in October had felt like “the end of the world” and forced residents to repair their damaged homes and neighborhood. Now they would have to do it again.

“We thought it was over. No more danger,” she said. “Now where can I go?”

Later on Saturday morning, Israel issued new evacuation warnings for the Dahiya.

The new wave of attacks on Lebanon came as Israel and Hezbollah appeared to be inching toward a cease-fire deal.

An Israeli official said Friday that there was “cautious optimism” about prospects for a truce in negotiations mediated by the United States, though Lebanese officials were less sanguine about a deal. Both Israel and Hezbollah have said they will keep fighting as negotiations go on.

Heavy fighting was reported overnight in the southern Lebanese town of Khiam which the Israeli military has been attempting to encircle in recent days, according to Lebanon’s state-run news agency. Hezbollah said on Friday that it had repeatedly attacked Israeli forces in and around the large town, which lies around three miles from the Israeli border.

Israel began an intensified military campaign against Hezbollah in September in response to almost a year of near-daily rocket attacks on northern Israel. Hezbollah said the attacks were in solidarity with its ally, Hamas, in Gaza. Both armed groups are back by Iran.

Israel said it was going to war in Lebanon to stop the rockets and to allow tens of thousands of displaced Israelis to return to their homes in northern towns that were evacuated last year. But the rocket attacks have not ceased, and those residents have been unable to return home.

The war has become the bloodiest conflict inside Lebanon since the country’s 15-year civil war, which ended in 1990.

Euan Ward, Ben Hubbard and Hwaida Saad contributed reporting.