A leading Hezbollah commander has reportedly been assassinated in Israel’s deadliest attack on Lebanon in recent days.

Hezbollah, Iran’s most powerful regional ally, has signaled privately that it does not intend to attack Israel, but Lebanon’s military has bolstered its presence in the country’s south to prevent rocket fire.

U.S. special envoy for Syria Thomas Barrack, who also serves as ambassador to Turkey, met Lebanese officials in Beirut as Iran and Israel traded more strikes in their days-long war and as the U.S. continues to press Lebanon to disarm Hezbollah.