CROWN POINT | The Lake County prosecutor's office charged a Chicago police officer Monday with armed intimidation stemming from an alleged September traffic confrontation.

The prosecutor filed papers Monday in Lake County Criminal Court naming 37-year-old Daniel Castillo in four felony counts that carry a maximum penalty of eight years in prison if convicted.

An affidavit says Castillo was in plain clothes and was in his private vehicle when he pulled a gun on another driver in Hammond.

Chicago News Affairs Officer Tom Polick declined comment Monday on the allegations.

Donald Curl, an investigator for the Indiana State Police, said officers were called in the early morning hours of Sept. 6 to a toll booth at the Calumet Avenue entrance to the eastbound Indiana Toll Road.

Trooper Chad Schuttrow states in court documents that he arrived to find Castillo driving a silver 2006 Nissan SUV and attempting to leave the scene. Hammond police officers reported they found a toll booth attendant upset and crying.

The trooper said Castillo was carrying a handgun in a holster and had a Chicago police badge on his belt.

Indiana State Police said Castillo told them he was driving in Illinois when a maroon 1998 Chevrolet Lumina cut him off in traffic. Castillo said he thought the driver might be drunk and followed the Lumina into Indiana to stop it, police said.

Court records identify John Sabovcik as the Lumina driver. Sabovcik is quoted in court records as saying Castillo was driving at high speeds and pointing a weapon at him. Sabovcik said he drove around several cars and through a couple of parking lots to get away. He said he thought he had escaped the SUV by driving into the Toll Road entrance and stopped to pay the toll, police reported.

Castillo told police he pulled up to the stopped Lumina, pulled out his loaded gun and was attempting to handcuff the driver when the toll gate opened and the Lumina drove off, court records allege.

The prosecutor alleges the toll booth attendant called for help and opened the gate for the Lumina. She said she was scared because Castillo didn't identify himself until after the Lumina escaped.

She and another witness said Castillo's car didn't have any emergency police lights activated.

Trooper Schuttrow reported Castillo said "that he and other police officers ... often make traffic stops, off duty, in their personal cars, out of uniform."