Video from a nearby business shows the moment the front of a building collapsed Wednesday at a strip mall, trapping six people behind a wall debris.

LA County fire officials say a 50-foot section in front of Beauty De Color Salon fell for unknown reasons around 4 p.m. People were trapped in an adjacent dry cleaners business and the salon east of Los Angeles.

Video from another business at the strip mall shows the front of the salon drop in a heap of dust and debris.

“It felt like an earthquake,” witness Justin Han said. “Started hearing squeaky noises. Suddenly the roof collapsed. Everybody started running to the back.”

Structural engineers are expected Thursday to help determine what caused the collapse and when repairs can begin.

Theressa Nguyen, the owner of Beauty De Color Salon was among six people rescued by firefighters.

“The noise was really loud,” she said. “We was stand up, walking inside. Finding someplace to hide. Luckily everyone was safe.”

Fire crews cleared a path through the debris because both impacted businesses lack back doors.

At least two parked cars were struck by debris.

A city inspector confirms a leg of the structure was red-tagged, meaning it’s unsafe for anyone to enter. Firefighters retrieved a fish tank at the salon owner’s request after someone told her it could be months before she’s allowed back inside.

“It felt like an earthquake,” said Justin Han, who was there for a haircut. “Started hearing squeaky noises. Suddenly the roof collapsed. Everybody started running to the back.”