Despite the weekend fire that burned many structures in the back lot of Universal Studios, the company’s theme park reopened to visitors Tuesday.

Fire investigators announced on Monday that the fire had been accidentally started by workers using a blowtorch on a movie set.

The workers had been using a blowtorch to heat asphalt shingles to apply to the roof of a building façade on Sunday, said Los Angeles County Fire Chief Michael Freeman, according to the Associated Press. After finishing the work, they followed the policy of standing watch for one hour, and then they left. About another hour later, a security guard noticed the fire and reported it.

The fire burned two blocks of the lot and much of the Courthouse Square set, which appeared in the films “Back to the Future” and “To Kill a Mockingbird.” The popular set for “King Kong,” which featured in the theme park tram tour of the back lot, was also reduced to ashes, together with a warehouse containing copies of archived TV shows and films. However, studios officials said all the material lost in the fire could be replaced.

About 400 firefighters tried to extinguish the fire. At least nine of them, and a sheriff’s department employee, suffered injuries, the Los Angeles County fire chief, P. Michael Freeman, said during a news conference on Monday.

The ruins can now even be considered a point of interest, as the first visitors of the reopened theme park could not help looking at the fuming ashes that replaced the former movie sets. The tourists on the park’s tram ride all applauded the firefighters as they drove past them.