A union for Chicago Transit Authority drivers says the operator 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 that the operator's call-in status without a consistent work shift caused her to work "strange" hours, which was a factor in the crash.
The CTA disputed the number of hours the operator worked, putting it at 55 hours.
Kelly says the operator is "torn to pieces" over the crash. He says the union will fight the CTA if it seeks to fire her.
A federal investigator looking into Monday's crash in which 32 passengers were injured.
The investigator says the operator acknowledged she dozed off before the accident.
Meanwhile the CTA said Friday it was "working around the clock" to reopen the O'Hare station and anticipated service would be restored sometime Sunday.