Investigators released the names on Saturday of the seven people who were killed in a massive pyrotechnics facility explosion in Northern California that took place days before the Fourth of July. The blast occurred in Esparto, about 40 miles from Sacramento, on July 1, triggering a series of massive explosions, according to the fire department.

The cause of the fire, which burned 78 acres, remained under investigation, according to Cal Fire, the state firefighting agency.