Blue Line trains were halted Saturday afternoon after a person fell on the tracks at the Division Street station.
Trains were standing at Division at 4 p.m. due to an unauthorized person the tracks, according to the Chicago Transit Authority. Some trains began moving by 4:20 p.m.
A male was recovered from the tracks, according to a spokespeople for the Chicago fire and police departments. He was transported to Northwestern Memorial Hospital in serious condition.
Police said he was still unidentified. Additional details have not been released.