UPDATED 12/19/11 8:19 a.m.

CHICAGO (CBS) — Two men were early Monday hospitalized after being shot on the city’s Northwest Side, in what was first believed to be a road rage incident but turned out to be a gang-related attack.

A woman was driving a car with two male passengers, when a man in a Pontiac Grand Am pulled up aside them around 12:20 a.m. Monday, according to Grand Central District police.

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They exchanged taunts and tensions reached a boiling point once the cars came to a stop at a traffic light at 6158 W. Fullerton Ave., near Riis Park, in the Belmont Central neighborhood, police said.

The male driver in the Grand-Am displayed a chrome handgun and fired into the other vehicle several times, hitting a 23-year-old man in the front passenger seat passenger twice in the rear shoulder. A 33-year-old man sitting in the back seat was shot once in each hand, police said.

The unidentified shooter fled southbound on Melvina Avenue.

The woman drove away with her two wounded passengers before calling authorities, police said.

She drove them West Suburban Medical Center in Oak Park, but the younger man was later transferred to Stroger Hospital of Cook County, police News Affairs Officer Hector Alfaro said.

The 23-year-old was in critical condition and the 33-year-old was in stable condition as of Monday morning, according to police.

Police initially called the incident a case of road rage, but now think the attack may have been gang-related.

No one was in custody for the attack early Monday.

The Sun-Times Media Wire contributed to this report.

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