Who is Hashem Safieddine, the alleged successor to Hezbollah's Hassan Nasrallah, killed by Israel?

Hashem Safieddine, whose death in an Israeli strike was announced Tuesday, was widely considered the potential successor to the group's assassinated leader Hassan Nasrallah. Nicholas Blanford, a Beirut-based Hezbollah expert and senior fellow at the Atlantic Council, also said Safieddine had "been touted as a potential successor to Nasrallah for years".