A flash fire Thursday at a California packaging plant sent one person to the hospital with severe burn injuries, KFSN News reports.

The fire happened at 3:45 p.m. at RePlanet Packaging in Visalia near Fresno, the Visalia Fire Department told the television station. Upon arrival, firefighters found an injured electrical contractor and a burning panel box outside the plant.

It was determined that the contractor was working on the box when the fire erupted. Firefighters had to wait until power could be shut down to the plant, allowing them to extinguish the fire.

Damage was estimated at $75,000, not include production lost while the plant was shut down.