ST. PAUL, Minn. (AP) -

Authorities investigating last month's shooting death of a Cold Spring police officer have announced a reward of up to $100,000 for information in the case.

The Minnesota Bureau of Criminal Apprehension announced the reward Monday, in hopes that someone comes forward with information that helps solve the case.

Thirty-one-year-old Officer Tom Decker was fatally shot Nov. 29 as he investigated a report of a possibly suicidal man. Police arrested a 34-year-old suspect, but he was released five days later.

Assistant BCA Superintendent Drew Evans says dive teams are again searching the Sauk River for a 20-gauge shotgun believed used in the killing.

Evans says authorities are also looking for information about a black minivan or van with a loud exhaust seen leaving the area at the time of Decker's death.