Iran's Supreme Leader, Ayatollah Ali Khamenei, has expressed significant concerns regarding Hezbollah's leadership after the reported death of its leader, Hassan Nasrallah. Following a deadly Israeli airstrike that targeted a bunker in which Nasrallah was present, Khamenei allegedly sent Brigadier General Abbas Nilforoushan of the Iranian Revolutionary Guards to advise Nasrallah to evacuate Lebanon. Both were killed in the attack. This incident follows a series of devastating explosions of Hezbollah's communication devices on September 17 and 18, intensifying the already strained relations between Israel and the Iran-backed militant group in Lebanon. Sources indicate that Khamenei is particularly worried about possible Israeli infiltration within senior ranks in Tehran. Immediately after the attack on Hezbollah’s communications, Khamenei reportedly referred to intelligence suggesting that Israel had agents embedded within Hezbollah, specifically targeting Nasrallah, according to a senior Iranian official. The ongoing turmoil has left Khamenei concerned not only for his safety but also about the growing mistrust between Hezbollah and the Iranian establishment. In light of the recent attacks, four Lebanese sources noted that the deaths of key Hezbollah figures are complicating the group's ability to select a new leader. There are fears that continued infiltration poses a risk to any successor. Magnus Ranstorp, a Hezbollah expert at the Swedish Defense University, commented on the implications of Nasrallah's assassination, stating, “Basically, Iran lost the biggest investment it had for the past decades... It shook Iran to the core. It shows how Iran is deeply infiltrated: they not only killed Nasrallah, they killed Nilforoushan.” An Iranian official revealed that Nasrallah's death has prompted Iranian authorities to investigate potential infiltrations within their own military and security structures. Suspicion has arisen concerning members of the Revolutionary Guards who frequently traveled to Lebanon, particularly after one individual began asking specific questions about Nasrallah's location. This person, along with others, has been arrested following alarms raised within Iran's intelligence community. Concerns about the infiltrator were heightened when his family reportedly moved outside of Iran. Another source emphasized that Nasrallah's assassination has led to widespread mistrust both between Tehran and Hezbollah and within the Hezbollah organization itself. According to one close to Iran's establishment, "The Supreme Leader no longer trusts anyone." Suspicion surrounding potential Mossad infiltration dates back to the assassination of Hezbollah commander Fuad Shukr, who was killed in July during an Israeli airstrike in Beirut while meeting with an IRGC commander. This incident was shortly followed by the assassination of Hamas leader Haniyeh in Tehran. Hezbollah is grappling with the fallout from Nasrallah's assassination, shocked by how effectively Israel managed to penetrate its ranks. Israel-Iran Tensions Escalate with Strikes in Lebanon; Iran Claims It Is Not Seeking War Reports Indicate Hezbollah Chief Hassan Nasrallah Suffocated After Israeli Airstrike in Beirut These Seven High-Ranking Officials Killed by Israel: What's More Implications for Hezbollah