The union representing Chicago Transit Authority motormen says the driver of the train that crashed at O'Hare International Airport worked 69 hours in the seven days before the accident.

Amalgamated Transit Union Local 308 President Robert Kelly said Friday the female operator's call-in status without a consistent work shift caused her to work "strange" hours, which was a factor in the crash.

Kelly says the operator is "torn to pieces" over the crash, and the union will fight the CTA if it seeks to fire her.

A federal investigator looking into the crash on Monday that injured 32 passengers says the train's operator acknowledged she dozed off before the accident.

Workers removed the train from the O'Hare station on Thursday. CTA officials say the station will reopen this weekend.

Brian Kersey, Getty Images