CHICAGO (CBS) — A 40-year-old man was shot and killed Sunday morning in the Heart of Chicago neighborhood.

Police said the man was found lying on the street near 21st and Paulina streets around 9:15 a.m. Sources said he had been shot 13 times.

READ MORE: Major Airlines Warn Of ‘Catastrophic Disruption’ To Travel And Shipping From 5G Debut Set For Wednesday By Verizon And AT&T

The victim was taken to Stroger Hospital of Cook County, where he was pronounced dead, according to police and fire officials.

READ MORE: Cook County Opening 3 Mass Vaccination Sites This Week

Police said the circumstances of the shooting are under investigation, but no one was in custody as of Sunday evening.

MORE NEWS: Man And Woman Dead In Naperville Murder-Suicide

Area Central detectives are investigating.