LOS ANGELES (AP) — 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 in which two people were detained, authorities said.

Flames lit up the sky before dawn in the North Hollywood area of the San Fernando Valley as fire spread through a 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 into the building, fire department spokesperson Nicholas Prange said.

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

Approximately eight other small blazes, including a car fire and rubbish fires, broke out in the same area within the span of an hour, Prange said.

All of the fires were being investigated by LAFD arson investigators but there was no immediate evidence connecting the blazes, he said.

The arson team was working with police and a “person of interest” was detained for questioning, Prange said. There was no additional information about that person.

The building that burned was the original Lamplighter Family Restaurant, a staple of the eastern San Fernando Valley for many years until it closed in 2006.