Unattended luggage left at Ogilvie Transporation Center was deemed safe after a police investigation halted trains and forced some to evacuate the station Wednesday morning.

Authorities said in a press conference Wednesday that a man at the station had an exchange with an employee at the ticket counter before leaving behind a brief case and a bag. A female custodian who witnessed the exchange, called the station's control center, which then called authorities.

Metra police responded to the scene with canine units as Chicago police and other state and federal angencies were called.

Metra confirmed police were called for assistance just before 10 a.m. Footage from the scene showed people leaving the building as officials confirmed part of the station was being evacuated.

Trains were stopped from entering and exiting the station as the investigation continued and the first two floors of the building were evacuated. All other offices were told to shelter in place, officials said.

A bomb unit x-rayed the bags and cleared it for explosives before the Chicago Fire Department checked them for chemical and biological agents and gave them the "all safe, all clear."

Once deemed safe, train service resumed and passengers were allowed re-entered the building just before 12:30 p.m. Metra warned riders to expect residual delays for about an hour, but said it expected schedules would be back to normal before the afternoon rush hour.