Ali Damush and Mustafa Mughniyeh have been named Specially Designated Global Terrorists.
Mughniyeh is a Hezbollah commander with extensive family links to the Lebanon-based militant group. He is the nephew of Hezbollah's previous military commander, Mustafa Badreddine, who was killed in an explosion near the Syrian capital in last year, and the son of military commander Imad Mughniyeh, who was killed in a 2008 car bombing in Damascus—both attributed to Israel.
Mughniyeh is also the brother of the late Jihad Mughniyeh, who was killed in an explosion in Quneitra in 2015, which was alleged to be an Israeli airstrike. At the time, he was Hezbollah's commander of the Syrian Golan sector.
Damush is an aide to the group's leader, Hassan Nasrallah. He heads the group's foreign relations department, which the State Department says "engages in covert terrorist operations around the world."
According to the State Department, Mughniyeh is in charge of the organization's operation in the Syrian Golan, where he has become a confidant and protégé of Badreddine. He is reported to be in charge of the security of high ranking officials in Lebanon, Syria and Iran.
It is thought that Mustafa's identity has been kept relatively secret, as opposed to his brother, in order for him to participate in operations such as those of Unit 910, which is responsible for overseas terror attacks.