A department spokesperson confirmed to Eyewitness News that investigators are examining claims that personnel circulated the images.
The explosion took the lives of detectives Joshua Kelley-Eklund, Victor Lemus and William Osborn.
READ MORE: Explosion kills 3 LASD deputies in East LA
3 LA sheriff's deputies killed in explosion at training facility
The department also told ABC7 that an employee was relieved of duty six months ago pending the outcome of the investigation.
No additional details about the inquiry have been released.