Two explosions went off outside the Iranian embassy in Lebanon on Tuesday morning, killing at least 23 people and wounding hundreds more. At least one Iranian diplomat, cultural attaché Sheikh Ibrahim Ansari, was reportedly among the dead. 

The Beirut neighborhood where the blasts took place is considered a stronghold of Hezbollah, which is an ally of both the Iranians and Syria's Bashar al-Assad. It is also home to many Shiite Muslims. An al-Qaeda-linked Sunni militant group, the Abdullah Azzam Brigades, that has been fighting against Assad's forces in Syria has claimed responsibility for the attack, although a statement from the Iranian government blamed Israel. Syria's government blamed Saudi Arabia.

Early witness reports suggest that a suicide bomber destroyed the main gate to the embassy, just before a second, more powerful blast, possibly a car bomb, went off nearby. Many of the surroundings buildings, including most of the embassy compound, were heavily damaged.

This is just the latest in a series of back-and-forth bombings between Shiite and Sunni groups in Lebanon, which is slowly turning into a second front in the Syrian civil war. Since Hezbollah began sending fighters to support Assad across the border, Sunni militants have stepped up their attack on Hezbollah supporters back in Lebanon — and now it seems they have gotten the Iranians more deeply involved. The conflict has long since stopped being just about Assad's brutal regime against his people, and has instead become a sectarian struggle stretching across the whole Middle East.