A conceal carry licensed holder returned fire critically wounding a man overnight at a gas station in the Englewood neighborhood, Chicago police said.

Shortly before 1:40 a.m. Saturday, a 36-year-old man and a 49-year-old man were involved in an argument at a gas station in the 200 block of West 63rd Street when the younger man retrieved a firearm from his vehicle and opened fire toward the older man, police said.

The older man returned fire striking the younger man to the arm. The 36-year-old was taken to St. Bernard Hospital where he was listed in critical condition, police said.

Police at the scene verified the older man was a CCL holder. Detectives were investigating.