According to NBC, before the incident, the fire department received a call, after which the rescuers went to the place of a possible transformer fire. The channel notes that after that at least three explosions occurred.

UPDATE: It appears there were multiple explosions in Huntington Beach at the Old World Village's Oktoberfest celebrations. https://t.co/crJ0SyJZgS (via @ kylen1972) pic.twitter.com/cpNjubCNOH

- NBC Los Angeles (@NBCLA) October 6, 2019

In September, a firefighter died in the American city of Farmington in a bombing at a center for adults with disabilities.