OAK FOREST, Ill.  (WBBM/CBS) — Autopsies were inconclusive on two elderly women who died Thursday when the car they were riding in collided with a Metra Rock Island District train, the Cook County Medical Examiner’s Office says.

The two Tinley Park women – 81-year-old Donna Grace and 97-year-old Gail Crabtree – were killed instantly when their vehicle drove through the gates and into the side of the train’s lead car at the Central Road crossing, near 167th Street, in unincorporated Oak Forest. 

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The collision caused the first train car to derail. Metra service was delayed during end-of-day rush hour Thursday.

The train’s video recorder clearly shows that the car was not in the crossing before the accident, and that the gates and flashers were working.  The wreckage of the auto became lodged beneath the cab car.

Grace was driving at the time of the crash. Published reports said a note was found at her home and addressed to her son, suggesting suicide as a possibility.  But a Cook County sheriff’s spokesperson on Friday said the department, which assisted in the investigation, did not find any suicide or “goodbye” note at Grace’s home.

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The autopsies were inconclusive, pending further investigation, the Cook County Medical Examiner’s office said.

Eight of the train’s 89 passengers required emergency room treatment at area hospitals, but their injuries were minor and no one was hospitalized overnight. 

The two women had just left a bingo hall, and had dropped off a third woman before the accident. 

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 Contributing: Sun-Times Media Wire