FOREST PARK, Ill. (CBS) — Four years after the murder of a Forest Park man, police have re-released a photo of a man they want to find and question.

As WBBM Newsradio’s Steve Miller reports, the body of David Carlson, 52, was found inside his garage behind his home in Forest Park. He had been shot in the head.

LISTEN: WBBM Newsradio’s Steve Miller reports

Police believe the motive was robbery.

“His pockets were gone through,” said Forest Park police Chief Jim Ryan. “His cell phone was taken.”

Carlson’s home was just two blocks from the Harlem Blue Line station.

Now police have again released a photo taken from Chicago Transit Authority security video of a man they want to question.

Ryan says that man transferred from the Blue Line to the Red Line soon after the murder.

“We actually looked at the video, and he appeared to be nervous,” he said. “He appeared to be looking at the cameras.”

Asked about DNA evidence, Chief Ryan says, “I feel confident that we have DNA from the scene.”

Anyone who can identify the man in the picture is asked to contact Forest Park police Detective Nicholas Petrovic immediately, at (708) 615-6236.

Cook County Crime Stoppers is also offering a $1,000 cash reward for information that leads to an arrest in the crime. Tips can be submitted anonymously to the Crime Stoppers hotline, at (800) 535-STOP.

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