The explosion, which occurred on a compound home to two fireworks companies and a gun dealer, sparked the 78-acre Oakdale Fire and prompted the county to declare a local health emergency. The coroner determined the men's deaths were "immediate."

Yolo County officials have now released their determination for what killed the seven people in July's Esparto fireworks facility explosion.

Officials have declared a local health emergency after the Esparto fireworks explosion that killed seven people in July.