Police say the gunman who killed a Colorado deputy had purchased 11 firearms from a Wyoming store between 2010 and 2013, but it wasn't immediately known whether any of those guns were used in the shooting.

A Laramie Police Department report shows Matthew Riehl bought weapons from Dave's Guns in Laramie.

Authorities in Colorado have not said what kind of weapon was used in the shooting Sunday that killed a deputy and injured four other officers and two civilians.

Store owner David Smith told police Riehl, a University of Wyoming law school graduate and Iraq war veteran, passed the required background checks at the time.

No one answered an after-hours call to the gun shop Wednesday.

Laramie police told The Associated Press they could not immediately provide a copy of the report Wednesday.

The purchase of the weapons coincided with Riehl's six-year descent from a budding attorney to a killer was accompanied by episodes of mental illness.

A document from the Veterans Affairs Department says Riehl was hospitalized at a VA psychiatric ward in Wyoming in 2014, and at one point he was placed under a 72-hour mental health hold there.

But the agency declined to say whether that treatment meant Riehl should not have been allowed to own a gun.

Federal standards prevent anyone from buying a gun who has been determined to be a danger to themselves or others by a court or other authority.