The Los Angeles County Sheriff's Department on Tuesday served a search warrant in Marina del Rey to follow up on leads stemming from the deadly explosion that killed three deputies.

The Bureau of Alcohol, Tobacco, Firearms and Explosives, along with the Los Angeles Police Department, assisted deputies in serving the warrant at the 4200 block of Via Marina. Deputies said they were hoping to determine the origins of the devices located at a Santa Monica complex.

LASD served a similar warrant on Monday, less than a mile away in the 13900 block of Marquesas Way. 

The deadly explosion happened on July 18 at the sheriff's Biscailuz Training Facility in East L.A. Senior law enforcement officials told CBS News that the LASD's bomb squad recovered at least one grenade in a Santa Monica garage along the 800 block of Bay Street the day before the explosion.

Deputies from the department's Arson Explosives Detail held the explosive overnight and were working to render it safe when it exploded. 

"There's a lot more that we don't know than we do know," Sheriff Robert Luna said last Friday, adding that it was too early to say what the deputies were doing when the blast took place. "But our intent is to look at this from the very beginning and figure out what is it exactly that caused this tragic event." 

The Sheriff's Department identified the deputies killed in the explosion as detectives Joshua Kelley-Eklund, Victor Lemus and William Osborn.

"There are no words to express the pain and sorrow we feel," Luna said. "These heroes represented the best of our Department, exemplifying courage, integrity, and selfless service. This is not only a heartbreaking loss for their families, but for all of us."