A US-made munition was used in a strike on central Beirut that killed 22 people and wounded 117, according to an analysis of shrapnel found by the Guardian at the scene of the attack.

The strike on Thursday night hit an apartment complex in the densely populated neighbourhood of Basta, levelling the apartment building and destroying cars and the interiors of nearby residences.

It was the deadliest strike on Lebanon’s capital city since fighting between Hezbollah and Israel started a year ago.

A first responder on the scene said rescue crews had worked overnight to find survivors and recover the dead from under rubble. They said the building had more people living there than usual as residents had recently welcomed people displaced from Israeli bombing in south Lebanon and the southern suburbs of Beirut. That elevated the number of people wounded and killed in the airstrike.