Oversight officials say the L.A. County Sheriff’s Department is blocking access to some shootings by deputies, despite state laws that authorize them to conduct meaningful investigations.

The department said it's working to confirm whether an apparent grenade discovered in Santa Monica on Thursday night caused the explosion that killed three deputies Friday.

Serving the search warrant were sheriff’s homicide investigators, the Bureau of Alcohol, Tobacco, Firearms and Explosives, and the Los Angeles Police Department. It was unclear exactly where the