TRENTON, N.J. (AP) — Three people believed to be members of the same Georgia family were killed in an accident Thursday the New Jersey Turnpike.

An 18-year-old woman, also believed to be a family member, survived.

Lt. Stephen Jones says police are still investigating what caused a tractor-trailer to hit the back of a Toyota Camry around 10 a.m. Thursday below Exit 5 near Mount Laurel.

VIEW: Photos From The Scene

Jones says the Camry’s 51-year-old male driver, a 49-year-old female and a 12-year-old male were all pronounced dead at the scene. The 18-year-old suffered minor injuries.

Police have not released their names but say they’re from Stone Mountain, Ga.

Jones says a second car was involved in a minor way, and a second tractor-trailer swerved to avoid the accident.

The southbound lanes of the Turnpike have re-opened.

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