MINNEAPOLIS (AP) — Search warrant documents say investigators were trying to buy a high-capacity pistol from Dolal Idd with help from an informant before the 23-year old was killed in an exchange of gunfire with Minneapolis police last week.

The shootout ensued Wednesday night when police tried to arrest the Eden Prairie man at a Minneapolis gas station. Police say body-camera video shows Idd shot first.

Authorities had previously said he was being sought in a weapons investigation, but the documents released Monday provided the first detailed account of why police were focused on him. A preliminary report Monday from the state Bureau of Criminal Apprehension also said Idd fired first.