An Israeli airstrike slammed into a densely populated residential area in Lebanon’s capital near key government and diplomatic buildings late Monday, killing at least five people as the U.S. pressed ahead with cease-fire efforts.

Lebanon’s state-run National News Agency said two missiles hit the area of Zoqaq al-Blat. The target of the airstrike remains unclear, and the Israeli army did not issue a prior warning.

The attacks came as Israel’s military has been pounding an area just outside the Lebanese capital with some of the heaviest waves of bombardment in months.

A new densely populated neighborhood in Beirut was hit by an Israeli air strike Monday evening, killing four people and wounding 18 others, according to the Lebanese Health Ministry.

An airstrike killed five people in central Beirut, and rockets fired from Lebanon killed one person in northern Israel and caused several injuries in a Tel Aviv suburb, amid a continuing U.S. push for a cease-fire deal between Israel and Hezbollah militants.

At least four people were killed and 18 others were wounded when an Israeli strike hit an area in central Beirut on Monday targeting an apartment building without any prior warning, eyewitnesses, security sources and the health ministry said.