CHICAGO (CBS) – CTA Blue Line trains are running again, after a suspicious package was found at the Addison Street Blue Line station on the city’s Northwest Side.

The briefcase shut down ‘L’ trains and parts of the Kennedy Expressway for several hours.

Police called in the Bomb and Arson Section to investigate, after a passerby reported a suspicious package with wires sticking out.

The briefcase, which was discovered at the CTA platform at 6 p.m., did not contain explosive materials, Grand Central Area Deputy Chief of Patrol John Escalante said.

Dispatch reports also indicated police investigated a nearby parked car in the vicinity of the 3600 block of West Addison Street. Escalante did not mention the vehicle.

As a precaution during the investigation, Illinois State Police closed the Kennedy Expressway in both directions until 8 p.m. The Addison ramps remained closed late Monday while Bomb and Arson detectives continued investigating. By early Tuesday, the ramps had reopened.

For a period of time, Blue Line service was cut off beyond Belmont. Service had returned to normal by Tuesday morning.

The Sun-Times Media Wire contributed to this report.

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