CHICAGO (CBS) — One man was killed and another was wounded late Sunday afternoon when a gunman opened fire on a Back of the Yards neighborhood sidewalk.

Police said around 5:45 p.m., a 56-year-old man and a 47-year-old man were on the sidewalk in the 1900 block of West Garfield Boulevard, when a suspect they didn’t know came up and opened fire.

The older man was shot once in the neck and was taken to the University of Chicago Medical Center, police said. He was pronounced dead at the hospital, police said.

The younger man was shot once in the elbow and was taken to the same hospital. His condition was reported to be stable.

There was no one in custody in the shooting as of Sunday evening. Area Central detectives were investigating.

As of Sunday evening, four people had been killed and 41 wounded in weekend gun violence in Chicago.