MELROSE PARK, Ill. (CBS) — Questions surround the recent homicide of a retired suburban police sergeant who is fondly remembered by his neighbors.

Former Melrose Park police Sgt. Ronald Susek was fatally shot in the backyard of his home on June 14.

Witnesses have told investigators that they saw a person leaving the area shortly after the shots were heard. In a news release, the police department did not provide a description of what the witnesses saw.

Police Chief Sam Pitassi emphasized the importance of the investigation.

“Sgt. Susek was near and dear to my heart and many at the department. The moment we found out it was a homicide, we pulled out all the stops. We are working with a number of different agencies, and are working a number of good leads,” he told CBS 2.

Susek, 61, was found by a neighbor in his backyard in the 1600 block of North 14th Avenue about 6:20 a.m. He suffered gunshot wounds and was taken to Gottlieb Memorial Hospital in Melrose Park, where he was pronounced dead.

It would be “probably impossible to find anyone to say anything bad about Ronnie Susek,” Earl Filskov, a friend and neighbor, told CBS 2’s Brad Edwards.

Filskov, himself a former cop, says the investigation had problems from the beginning when investigators failed to collect all evidence from the outside crime scene.

“It’s all subject to the elements. The longer it sits outside, it deteriorates and it loses its usefulness,” Filskov said.

The medical examiner’s office ruled the shooting was a homicide.

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