LAPLACE - State police say a woman was pregnant with twins when she and her 7-year-old son died in a crash Monday.

According to Louisiana State Police, the crash happened shortly before noon on I-10 near Belle Terre Boulevard in Laplace. Tyandra Lewis, 27, and her son were both killed in the collision.

Investigators believe Lewis was driving eastbound on the interstate when her car came to a stop in the left lane. A truck traveling that same direction slammed into the rear of the vehicle and killed the mother and child.

State police confirmed Lewis was also pregnant with twins.

A front seat passenger and his 3-year-old child survived the crash without serious injuries. 

Impairment is not suspected in the crash at this time. The incident remains under investigation.