Two suicide bomb blasts killed at least 37 people and injured over 180 others in a stronghold of Lebanon’s Shiite Hezbollah movement in Beirut on Thursday evening. According to police, two suicide bombers set off the blasts in front of a crowded shopping centre in the southern Beirut suburb, Burj al-Barajneh. The Sunni jihadist Islamic State released a statement taking responsibility for the attacks, which are said to be the worst such blasts in 25 years, since the civil war.

Agence France-Presse said that the body of a third bomber was found near the blast site, who had died before he could set off his own bomb vest. The bombings followed a series of attacks on Hezbollah strongholds in 2014 after Hezbollah fighters joined Syrian forces against a Sunni uprising.

Lebanon Prime Minister Tamman Salam called for a day of mourning on Friday. Hezbollah is a Syrian ally in the fight against Islamic State, which could have been the reason behind the blasts, said officials.