A raging fire destroyed a vacant commercial building in Los Angeles early Wednesday and numerous other small fires broke out in the same area, triggering an arson investigation, authorities said.

Flames lit up the sky before dawn in the North Hollywood area of the San Fernando Valley as fire spread through the former restaurant, blanketing the neighborhood with smoke.

More than 100 firefighters battled the flames. Some perched high on ladders to direct streams of water into the building. The Los Angeles Fire Department also deployed its robot firefighting vehicle, spokesperson Nicholas Prange said.

The building sustained heavy damage and substantially collapsed, but no injuries were reported, Prange said.

Ten other fires broke out within an hour in roughly a half-mile (0.8-kilometer) radius and two “persons of interest” were detained, Capt. Erik Scott, a fire public information officer, said in a social media post.

The Police Department also tweeted that two persons were detained, but gave no further information about them.

The gutted building once housed the Lamplighter Family Restaurant, a longtime fixture in the eastern San Fernando Valley until it closed in 2006.

George Metsos came to look all that was left of the restaurant his parents opened in the 1970s and where he started in the family business right out of high school.

“I came here because I just can’t believe that this is the way it’s coming down — yeah, it’s unbelievable,” he told KTLA-TV.

Submitted by Associated Press