WASHINGTON — As the conflict intensifies between Israel and Hezbollah, the US State Department is exploring options for a possible evacuation should the situation deteriorate, while urging American citizens to depart Lebanon via commercial flights while they still can. 

Adding to the urgency on Tuesday was Iran’s launch of nearly 200 missiles at Israel in retaliation for a string of Israeli assassinations of militant leaders, including the airstrike that killed Hezbollah leader Hassan Nasrallah. An Israeli military response is expected in the coming days, heightening the risk of all-out war a week after the United States and France proposed a 21-day cease-fire aimed at cooling tensions along the Israel-Lebanon border. 

The State Department is working with airlines to secure additional flights out of Lebanon, where Israel overnight Monday began its ground invasion targeting Hezbollah militants in the country’s south. Lebanon’s sole commercial airport, Beirut Rafic Hariri International Airport, remains open even as an increasing number of international airlines suspend service to and from the country. Ticket prices on available flights have skyrocketed. 

As of Tuesday afternoon more than 6,000 American citizens in Lebanon had registered with the State Department to receive further information on the security situation and possible departures.