Police are trying to piece together how an argument in a Waldo neighborhood exploded into a fatal shooting Saturday afternoon.
Authorities said a man in his mid-50s was killed in the 200 block of West 78th Street shortly before 3 p.m.
The man was found sprawled on the lawn of a home where emergency crews tried unsucessfully to keep him alive.
Shortly afterward, police apprehended a suspect, a male in his late 30s, who had fled southward after the shooting. The suspect had not been charged as of early Saturday night, a police spokesman said.
Details of what led to the shooting were unclear Saturday night. Police did say robbery was not a factor and the two men were not related. They said they did not know what started the argument.