CUDAHY ( — Four firefighters were recovering Friday after falling through the roof of an abandoned casino in Cudahy.

 The 3-alarm fire started around 11:30 p.m. Thursday at the Club Caribe Casino on Atlantic Avenue near Hartle Avenue, officials said.

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Firefighters were on the roof of the building battling the flames when part of it gave way.

Members of the Rapid Intervention Group, who were on standby and trained to rush into burning buildings, ran in and rescued the four men.

“The firefighters ran back to their truck to get their tools, I guess, to get in because they said firefighters were trapped in there,” a witness said.

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The four men were pulled out and rushed to the County USC Medical Center burn unit.

Three were treated and released a few hours later. The fourth remained hospitalized with burns but was expected to survive.

The casino has been closed for about five years. The property had recently been put up for sale and a fence was surrounding it to try and keep out squatters, according to neighbors.

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“Fire investigators are sifting through the rubble trying to figure out what sparked the fire in this building that’s been vacant for five years,” Randy Wright from the LA County Fire Department said.