CHICAGO (CBS) — Residents in the Rogers Park neighborhood are in mourning, and searching for answers, a day after a 73-year-old man was shot and killed while walking his dogs.

“We’re devastated. There’s no words that I can even convey for something like this,” said Rogers Park resident Bruno Mondello.

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Police said 73-year-old Douglass Watts was out walking his two small dogs around 10 a.m. Sunday, when a masked man shot him in the head, killing him near Sherwin Avenue and Sheridan Road. Investigators believe the killer might have robbed Watts before shooting him.

On Monday, flowers marked the spot in Rogers Park where Watts was gunned down. Neighbors demanding justice said they plan to canvass the area, looking for answers.

“I don’t necessarily know what the answer is, but I know that we have to at least try and do something. Something is better than nothing,” Rogers Park resident Fallon Sowers said.

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Ald. Joe Moore has said police will review surveillance video from the area, and witnesses have provided descriptions of the shooter to police.

He added that neighbors can expect to see more patrols in the area and that some of the best officers work here and are working on this case.

“There are a lot of good leads and hopefully we can have enough information to apprehend who did this horrible deed,” said Moore.

Neighbors believe the dogs were later retrieved and are with one of the victim’s loved ones.

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A $1,500 reward is being offered for information leading police to the shooter.