BEIRUT >> The Israeli military kept up its heavy bombardment of a once densely populated area adjoining Beirut on Friday after saying its ground troops were battling new targets in southern Lebanon, signaling a widening of the fighting that could further undercut cease-fire efforts.

The airstrikes on the Dahiya area, south of Beirut, where the militant group Hezbollah holds sway, were the latest in a string of bombings this week. The Israeli military issued new evacuation warnings just after dawn Friday, and missiles began landing soon afterward, leveling at least one high-rise residential building that had been identified in the warnings and sending a thick dust cloud through the surrounding streets.

There were no immediate reports of casualties. Most residents fled the Dahiya weeks ago, when Israel’s bombing campaign began.

There were also signs that Israel’s ground invasion was broadening and that its troops were battling Hezbollah fighters deeper inside Lebanese territory.

The Israeli military said Thursday that its commandos were conducting ground operations against “several new enemy targets” in Lebanon. A senior Lebanese security official, speaking on condition of anonymity to discuss sensitive military matters, said Israeli ground forces were operating around the town of Chamaa, roughly 3 miles from the border.

Hezbollah also said overnight that it had attacked Israeli soldiers near Tayr Harfa, a town south of Chamaa that it described as part of its “secondary line” of defense and where clashes had not been previously reported. On Friday, the group said it had fired rockets at Israeli troops on the outskirts of Talloussah, another town where fighting had not been previously reported.

A widening Israeli offensive would undermine U.S. diplomatic efforts to stem the conflict between Israel and Hezbollah, which is backed by Iran. The Biden administration has renewed a push to contain the fighting after rounds of shuttle diplomacy over the past year failed.

Israel has demanded that Hezbollah withdraw from areas near the Israel-Lebanon border as part of any truce. Israel has also insisted that any cease-fire deal preserve its right to attack Hezbollah again should the group violate the terms of a truce, a stance that the Lebanese government and Hezbollah strongly oppose.

There has been no public indication that Hezbollah or its patron, Iran, are willing to acquiesce to Israel’s demands.

While Hezbollah’s leaders and weapon stockpiles have been hit hard, the group still poses a formidable threat, firing rockets and drones into Israel daily and killing six Israeli soldiers Wednesday in southern Lebanon.

A prominent Iranian official, Ali Larijani, met Friday with Lebanese officials in Beirut to discuss the cease-fire efforts, the Iranian Embassy in Lebanon said.