"Due to the unpredictable nature of ongoing conflict between Hezbollah and Israel and recent explosions throughout Lebanon, including Beirut, the US Embassy urges US citizens to depart Lebanon while commercial options still remain available," the State Department said in an updated advisory.

"At this time, commercial flights are available, but at reduced capacity. If the security situation worsens, commercial options to depart may become unavailable," it added.

In late July, the United States raised its travel advisory for Lebanon to its highest "do not travel" classification, after a strike on southern Beirut killed a top Hezbollah commander.

Israel on Friday struck southern Beirut again, saying this time it had killed the head of Hezbollah's elite Radwan Force and several other commanders.

The Lebanese health ministry said 37 people were killed in the strike, which followed sabotage attacks earlier in the week on pagers and two-way radios used by Hezbollah, which killed dozens and wounded thousands. 

Iran-backed Hezbollah has blamed Israel, which has not commented.

Hezbollah fighters have traded cross-border fire with Israel for nearly a year in stated support of Palestinian ally Hamas, whose October 7 attack on Israel triggered the ongoing war in Gaza.

But the exchanges have escalated in recent weeks, as Israel turns its attention to its northern border after significantly weakening Hamas.

The US State Department reiterated Saturday that Americans should "immediately" leave southern Lebanon, as well as areas near the Syrian border and refugee settlements