CUDAHY, Calif. (KABC) --

Four firefighters were injured after they fell through a roof while battling a three-alarm fire at an abandoned casino in Cudahy.

The blaze at the Club Caribe Casino ignited around 11:30 p.m. Thursday on the 7600 block of Atlantic Avenue.

The firefighters were on the roof to cut a hole for ventilation when it gave way. They fell through and had to be rescued by fellow firefighters.

Los Angeles County Fire Department officials said the roof collapsed like a slide, and the firefighters slid down. This minimized the firefighters' injuries, but the incident was still very intense.

"It's very terrifying. These are guys that I've worked with day in and day out. This is actually my old crew here, so I know all the gentlemen involved in this incident," said Chris Reade with the Los Angeles County Fire Department. "When you're up on that rooftop and you start hearing creaking from that wood, I can't imagine. It's never happened to me, but I can't imagine what was going through their mind at first."

All four firefighters were transported to local hospitals. They suffered minor injuries and will be OK.

An investigation is underway to find out why the roof collapsed. Authorities will look into whether structural failure or the actual fire caused the collapse.

The cause of the fire was unknown. Arson specialists are investigating the incident.