MASON, Ohio — An Ohio coroner says preliminary findings indicate the death of a 15-month-old girl who was left inside a car by her mother as the woman worked in a nearby office building was heat-related.

The mother found the girl motionless around 5 p.m. Wednesday in the parking lot of Procter & Gamble offices in the southwest Ohio city of Mason. The mother is a Proctor & Gamble employee but hasn’t been identified.

She made a frantic 911 call, telling the dispatcher her daughter was dead when asked to perform CPR.

The Warren County prosecutor said Thursday that any discussion of criminal charges against the mother would be premature until Mason police complete their investigation.

A coroner’s investigator said a small child would be especially susceptible to heat in such a situation.