Iran's Quds Force commander Esmail Qaani has not been heard from since Israeli strikes on Beirut late last week; two senior Iranian security officials told Reuters.
Here are some facts about Qaani:
Tehran named Qaani the head of the Revolutionary Guards Corps' overseas military intelligence service after the United States assassinated his predecessor, Qassem Soleimani, in a drone strike in Baghdad in 2020.
Part of Qaani's task in that post has been to manage Tehran's proxiesa across the Middle East and other regions around the world.
While Soleimani held the reins of the Quds Force during a time when Iran's proxies - from Lebanese Hezbollah to Iraqi Shi'ite militias to the Houthis of Yemen - grew their power in the Middle East, Qaani has presided over their battering at the hands of Israeli spies and warplanes.
Qaani became deputy commander of the Quds Force, the overseas arm of Iran's Revolutionary Guards, in 1997 when Soleimani became the Force's chief commander.
When Qaani took over, he vowed to boot US forces out of the Middle East in revenge for Soleimani's killing. "We promise to continue martyr Soleimani's path with the same force ... and the only compensation for us would be to remove America from the region," state radio quoted Qaani as saying ahead of Soleimani's funeral in Tehran.
Qaani, 67, was born in Mashhad, a conservative Shi'ite Muslim religious city in northeastern Iran.
Qaani has also overseen operations beyond Iran's eastern borders, including Afghanistan and Pakistan. He does not speak Arabic.