COLD SPRING, Minn. (AP) — Minnesota authorities are still looking for the gun used to kill a Cold Spring police officer this week.

The Stearns County sheriff’s office put out a request Saturday asking members of the public to keep on the lookout for a discarded weapon. They believe the firearm used was a 20-gauge shotgun.

Authorities are asking Cold Spring residents to check their yards and areas around their homes. The sheriff’s office says anyone who finds the weapon should leave it untouched and call 911.

Detectives are investigating the shooting of Officer Tom Decker, who was ambushed late Thursday after being called to check on a man’s welfare. Investigators say several guns were found, but they’re still looking for the presumed murder weapon.

The 34-year-old shooting suspect was taken into custody Friday.

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