Police officers work at the site of an Israeli strike, amid ongoing cross-border hostilities between Hezbollah and Israeli forces, in Kola, central Beirut, Lebanon September 30, 2024. (Photo: REUTERS)

The Popular Front for the Liberation of Palestine (PFLP) said the three leaders were killed in a strike that targeted Beirut's Kola district.

Israel's increasing frequency of attacks against the Hezbollah militia in Lebanon and the Houthi militia in Yemen have prompted fears that Middle East fighting could spin out of control and draw in Iran and the United States.

The PFLP is another militant group taking part in the fight against Israel.

Israel on Sunday launched airstrikes against the Houthi militia in Yemen and dozens of Hezbollah targets throughout Lebanon after earlier killing the Hezbollah leader.

The Houthi-run health ministry said at least four people were killed in airstrikes on Yemen's port of Hodeidah, which Israel said were a response to Houthi missile attacks.

In Lebanon, authorities said at least 105 people had been killed by Israeli air strikes on Sunday. Lebanon's Health Ministry has said more than 1,000 Lebanese have been killed and 6,000 wounded in the past two weeks.

The intensifying Israeli bombardment over two weeks has killed a string of top Hezbollah officials, including its leader Sayyed Hassan Nasrallah.