A Cicero police officer was shot Thursday on the city’s Southwest Side.

Officer Luis Duarte, who was involved in an investigation at the time, was shot multiple times near I-55 and Cicero Avenue about 5:17 p.m., authorities said. He was taken to the hospital and was expected to undergo surgery.

Police said Duarte and his partner attempted to pull over a vehicle as it was in traffic attempting to get on the expressway. The vehicle would not stop, so the officers boxed it in with their cruiser, police said. The driver of the suspect vehicle got out and began shooting at the two officers who were in their squad car, police said. Duarte, 31 years old and a four to five year veteran of the force, was struck multiple times.

At some point during the exchange of gunfire with police, a citizen who police said is authorized to carry a concealed weapon was in the area and began shooting at the suspect with the police. The suspect was hit at least once by gunfire but it was not known if Cicero police or the armed citizen fired that shot, police said.

The suspect was in Chicago police custody.

A Cicero police officer has been shot during a police investigation in Chicago at I-55 and Cicero Ave. Officer condition is unknown. Please avoid the area and make way for emergency vehicles as intermittent closures will be in effect. pic.twitter.com/WdCcRpfKZg — Anthony Guglielmi (@AJGuglielmi) September 13, 2018

"Please avoid the area and make way for emergency vehicles as intermittent closures will be in effect," Chicago police spokesman Anthony Guglielmi tweeted.

The Illinois State Police were investigating the officer-involved shooting aspect of the case, per standard procedure, officials said.