CHICAGO (CBS) -- An off-duty Chicago police officer has died, after crashing an ATV in the West Ridge neighborhood Tuesday evening.

Police said, around 5:45 p.m., a 29-year-old man was driving an ATV east on the 2500 block of West Bryn Mawr Avenue, when he tried to go around a Honda SUV, and slammed into it.

The off-duty officer was taken to St. Francis Hospital in critical condition, and later died of his injuries.

The Cook County Medical Examiner's Office later identified the man as Raheem Mills, 29.

Police said they are investigating the crash.

According to the Illinois Farm Bureau, it's illegal to operate ATVs on city streets.