This family photo shows slain Cold Spring, Minn. police officer Tom Decker. AP Photo/Family Photo via The St. Cloud Time

A man who killed himself in January would have been arrested for killing Cold Spring, Minn., police officer Tom Decker, state officials said Tuesday.

Evidence supported the arrest of Eric Joseph Thomes, who killed himself on January 2, the state Bureau of Criminal Apprehension and Stearns County sheriff's office said. Thomes would have been arrested for Decker's murder if he was still alive, BCA spokesperson Jill Oliveira said.

The BCA also said there is not sufficient evidence to charge another man, Ryan Michael Larson, who was arrested after Decker's murder but later released and not charged. He is no longer a suspect, Oliveira added.

• NewsCut: Time for an apology for Ryan Larson

Decker's murder case is being left open. But the active portion of the investigation is now over and no new leads are being pursued, the agencies said. Instead, investigators are once again appealing to the public for more information.

Decker was killed behind Winner's Bar in Cold Spring in November 2012. In January, police say they went to question Thomes, who lived on the outskirts of Cold Spring and had already been interviewed repeatedly.

When investigators arrived on his property, police say Thomes fled into a building where he hanged himself.

During a search of a property police say "Thomes would've had access to," they found the 20-gauge shotgun they say was used to kill Officer Decker. Up until Tuesday, authorities had identified Thomes only as a person of interest.

Larson was arrested the night Decker was killed and held for an extra day, but he was never charged.

"Although sufficient probable cause existed to arrest Ryan Michael Larson, continued investigation did not reveal sufficient evidence to charge Mr. Larson," the BCA said in a prepared statement. "At this time, the investigation has provided no information that Mr. Larson participated in Officer Decker's murder."

The investigation was a challenge from the start. Not only did police release their primary suspect for lack of evidence, but it took investigators weeks to recover the murder weapon.

Details that emerged raised more questions about what took place the night Decker was killed.

Decker and Greg Reiter, another officer, were making a welfare check on Larson. According to court documents, Reiter was in his squad car when he heard two shots and saw a white male standing over Decker holding a hand gun in a shooting position. Reiter put his vehicle into reverse and watched the suspect walk away in the opposite direction, the documents said.

Larson has moved from his Cold Spring apartment.

Since his arrest, he said he's been diagnosed with post traumatic stress disorder, depression and anxiety.

Larson said he hopes the BCA announcement is a turning point. "The damage has already been done," he said.

"Investigators brought me in the night of the murder. They talked to me 'til five or six in the morning, threw me in a cell and never once talked to me again," he added. "I think it was pretty clear to them very early on in the investigation that I had nothing to do with it."