Officers responded just after midnight to assist Indiana State Police in a traffic stop on I-80/94 east of the Indiana/Illinois state line.
Police said a driver took out a handgun and fired at an Indiana State trooper, two Lake County Sheriff's officers and a Hammond police officer.
The suspect, a 34-year-old man from Gary, was killed at the scene and a trooper was shot in the chest.
The trooper was transported to a hospital in Munster and transferred to the University of Chicago Medical Center, where he was in stable condition, police said.
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The trooper was transported to Munster General Hospital and transferred to the University of Chicago Medical Center, where he was in stable condition, police said.
Police said they are expecting the trooper to make a full recovery. The trooper has been with the department for eight years.
Indiana State Police update eon I-80/94 shooting
Indiana State Police said eastbound lanes on I-94 are closed with traffic being diverted at Calumet Avenue and Indianapolis Boulevard.
No other officers were injured. A 34-year-old woman who was in the vehicle was taken into custody.