MASON, Ohio -- A toddler left in a vehicle in the Procter & Gamble Business Center's parking lot in Mason died Wednesday afternoon.

Warren County Coroner's Office investigator Doyle Burke said the toddler's mother, a P&G employee, left her child unattended in the car all day. She called fire crews at about 5 p.m. to report the toddler was no longer breathing. By the time crews arrived, the 15-month-old girl was dead in the back seat.

The preliminary findings of the autopsy, completed by Dr. Russell Uptegrove from the Warren County Coroner's Office, were consistent with a heat-related death.

"Certainly a 15-month-old is more susceptible to something like this than an adult," Burke said. "Any time something happens like this, it's preventable. It's a wakeup call to anyone who has children: Just be careful."

RELATED: Toddler's death in Mason mirrors situation exactly one decade ago

MORE: Miamisburg-based Evenflo's car seat designed to save babies from hot car dangers

The mother's identity has not yet been released and no charges have been filed.

"We are aware of a tragic accident that took place on the campus of P&G’s Mason Business Center earlier today," P&G said in a statement. "Our thoughts and prayers are with the affected family. We are providing our full support and cooperating with local officials."

A spokesperson for P&G said the company does not have a daycare.