A 3-year-old boy died when his dentist father left him inside a sport utility vehicle (search) for three hours, officials said.

Dr. Dennis F. Sierra took his son Andres to work with him Thursday and left the boy in the car, intending to be in the office for only a short time, Palm Beach County sheriff's spokeswoman Diane Carhart said.

A relative called Sierra about three hours later to ask about the boy, and the father and office employees rushed to the car to find Andres was not breathing.

The boy died about an hour later at West Boca Medical Center (search).

It was not immediately known if any charges would be filed. Sierra was not arrested Thursday, said his lawyer, Michael Salnick.

"This is an absolute tragedy, a nightmare," Salnick said. "Total devastation is the only way to describe how Dr. Sierra feels."

An autopsy was planned.