Delays are expected to be extensive, but the exact duration is unknown, Metra said.
BNSF trains were allowed to enter and exit Union Station again around 5:20 p.m. But several trains scheduled to depart on or around 6 p.m. were canceled.
A train scheduled to arrive in Aurora at 4:16 p.m. fatally struck a pedestrian around 3:30 p.m.
Metra had temporarily implemented its overcrowding prevention plan at Union Station, when all passengers of affected lines are sent to the station's Great Hall.
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