The explosion has thundered at Huntington Beach Oktoberfest

A pillar of fire escaping from a transformer caused damage to 4 people nearby. Two firefighters and two festival visitors were taken to hospital with injuries of varying severity.
According to a report from the Fire Department at Huntington Beach, they received a message about a sparking transformer box. A team of four rescuers, who arrived at the site of the fire, opened the entrance to the premises and was thrown back several meters by a strong explosion.
Eyewitnesses said that during a fire extinguishing, three consecutive explosions were distinctly audible and a column of fire flew up to a height of about 10 meters. Video from the scene shows the moment the door was opened.
It is reported that the incident occurred after 8 pm. At the moment, the police and the fire department are investigating the scene of the fire. It is unclear what caused the explosion, but authorities suggest that high-pressure cooling oil could erupt due to power overloads.
A series of explosions has rocked an Oktoberfest celebration in Huntington Beach, California leaving multiple people injured, including 3 firefighters. https://t.co/NwTTxhhlmA pic.twitter.com/STIqlLo7Uc
— ABC News (@ABC) October 6, 2019