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.

Qaani traveled to Lebanon after the assassination last month of Hezbollah leader Sayyed Hassan Nasrallah in an Israeli airstrike.

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 paramilitary allies across the Middle East and other regions worldwide.

- According to people familiar with Qaani and Soleimani and Western military and political analysts, Qaani has never commanded the same respect as his predecessor, Soleimani, or maintained the same close relationships among Iran's allies in the Arab world.

- While Soleimani held the reins of the Quds Force during a time when Iran's proxies - from Lebanese Hezbollah to Iraqi Shi'ite Muslim 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 U.S. 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. He fought for the Revolutionary Guards during the Iran-Iraq war in the 1980s.

- Qaani has also had experience of overseas operations beyond Iran's eastern borders, including Afghanistan and Pakistan. He does not speak Arabic, unlike Soleimani, who spoke fluently with Iraqi militias and Hezbollah commanders.

- He has adopted less public persona than Soleimani, and little information is available online or in leaked diplomatic cables.

- Unlike Soleimani, who over the years was widely photographed on battlefields in Iraq and Syria alongside the militias Tehran has armed and trained, Qaani has preferred to keep a lower profile and conduct most of his meetings and visits to neighboring countries in private.