Twin suicide bombings struck a southern Beirut suburb that’s a stronghold of the militant Shiite Hezbollah group on Thursday evening, killing at least 43 people and wounding scores more in one of the deadliest attacks in recent years in Lebanon.

The attack was quickly claimed by the extremists Islamic State group, which is fighting in neighboring Syria and Iraq but has not had a recognised affiliate in Lebanon, though the tiny Mediterranean country has seen deadly spillovers from the civil war next door.

The explosions hit minutes apart during rush hour in an area of southern Beirut called Burj al-Barajneh, a Hezbollah stronghold. The Shiite group has been fighting in Syria along with Syrian President Bashar Assad’s forces. The area has been hit in the past and Sunni militant groups have threatened to carry out more attacks there.

Along with the 43 killed, the bombings also wounded 239 people, the Health Ministry announced.

It was not immediately clear how many attackers were involved. According to a Lebanese security official, the first suicide attacker detonated his explosives’ vest outside a Shiite mosque, while the second blew himself up inside a nearby bakery.

An apparent third attacker was found dead, his legs blown off while he still wore an intact explosives’ belt, said the official, speaking on condition of anonymity in line with regulations. The official speculated that the third man may have been killed from the explosion set off by the second bomber, as he was reportedly close to that blast.

The Al-Mayadeen TV also reported there was a third would-be bomber, and showed a video of a bearded young man with an explosives’ belt. The report said he died before he was able to detonate his explosives.