A couple and one of their children died when a tractor trailer in Central Florida

A couple and one of their children died when a tractor trailer struck their vehicle at an intersection in central Florida. Two other children were critically injured.

The crash happened early Tuesday in Polk City after the family's car apparently ran through a stop sign. It was dragged some 400 feet.

Polk County Sheriff's deputies say the deceased child was in the front seat.

Two children in the back seat were airlifted to Arnold Palmer Children's Hospital in Orlando in critical condition. An infant was taken to a hospital with non-serious injuries.

Investigators are trying to locate the couple's out-of-state relatives before names are released.

The intersection was shut down for hours as authorities investigated the crash. All roads are now open.

Further details were not immediately available.