Kevork Djansezian/Getty Images(CNN) - An underground electrical vault exploded at a restaurant in Huntington Beach, California, Saturday, leaving four people injured.
The explosion took place during an Oktoberfest celebration at the Old World restaurant, where firefighters initially responded to a report of an electrical fire, Huntington Beach Fire Battalion Chief Jeffrey Lopez said.
An underground electrical vault exploded as firefighters went to open it, Lopez said.
Huntington Beach firefighters worked to evacuate all of the restaurant's patrons and made sure the fire was under control, Lopez said.
Two firefighters and two civilians were injured in the explosion.