At least 40 bullet fragments were collected at Annunciation Catholic Church in southwest Minneapolis by law enforcement following the mass shooting on Wednesday that killed two kids and injured 21 other people.

According to a search warrant filed Thursday in district court, the fragments were found around the pews and sanctuary of the church. Police also found at least 10 ammunition magazines, including three empty rifle magazines, three full rifle magazines and three full pistol magazines.

A Mossberg pump-action shotgun, a Taurus semi-automatic 9mm pistol, a Magpul semi-automatic rifle and a knife were collected at the scene, according to the warrant.

The shooter, identified as 23-year-old Robin Westman of suburban Minneapolis, recently bought the three guns legally and does not have any known criminal history, according to Minneapolis Police Chief Brian O'Hara.

The shooter died by suicide and was found near the back of the church along with a shotgun, rifle and a 2x4 piece of wood with what appeared to be smoke canisters attached to it, according to the court document. 

According to the warrant, a cellphone with documents belonging to the shooter was found in a Dodge Ram utility van parked in the back parking lot of the church.

The warrant said the Minneapolis Police Department has obtained video "showing at least a portion of the shooting."

The shooter visited the church weeks before the shooting and apparently conducted surveillance there, according to a Minnesota official and a federal law enforcement source with knowledge of the investigation.  Police have not identified a motive, although investigators say a review of Westman's writings revealed an obsession with mass shooters.

Eight-year-old Fletcher Merkel and 10-year-old Harper Moyski were killed in the shooting. Eighteen other kids and three adults in their 80s were injured. 

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