Iran smuggled weapons and military equipment to Syria under the guise of earthquake relief flights, aimed at strengthening Syria’s defenses against Israel and supporting President Bashar al-Assad, with Israel carrying out targeted strikes against the shipments. 

Iran has been using earthquake relief flights to smuggle weapons and military equipment into Syria, according to Syrian, Iranian, Israeli, and Western sources. The aim of this operation was to strengthen Syria’s defenses against Israel and to support President Bashar al-Assad. The supplies included advanced communications equipment, radar batteries, and spare parts required for an upgrade of Syria’s Iran-provided air defense system. Israel became aware of the weapons flow into Syria and carried out targeted strikes against the shipments, relying on specific intelligence. The Iranian mission to the United Nations denied the claims. 

Source: https://www.reuters.com/world/middle-east/iran-exploits-quake-relief-mission-fly-weapons-syria-sources-2023-04-12/