The strike was the first near the Lebanese capital since a cease-fire that has curbed fighting but not halted it. Washington is pushing for a lasting peace, hoping it will ease diplomacy with Iran.

Iran’s foreign minister has already arrived in the country, state media reported. He was believed to be carrying a written response to a U.S. proposal to end the war.

The U.S.-mediated cease-fire halted an all-out war between Israel and Hezbollah, but their intensifying attacks on each other could put the truce at risk.