GARY, Ind. — A six-year-old girl is dead and two other children are seriously injured after a mail truck reportedly rear-ended a stopped car on Interstate 80 in northern Indiana early Wednesday.

According to Indiana State Police, the accident occurred at approximately 1:30 a.m. when a Volvo semi truck pulling a trailer loaded with U.S. mail rear-ended a Nissan Altima near mile-marker 7.5 on I-80.

State police said the Altima had been stopped in the right lane. Two adults and three children were in the Altima at the time of the collision.

State police said the driver of the Altima, a 27-year-old from Milwaukee, was transported for life-threatening injuries. The six-year-old girl reportedly died while being transferred. The other adult and two children who were in the Altima sustained “serious, life-threatening injuries” and were either treated locally or flown to a hospital for specialized treatment, state police said.

The driver of the semi, a 49-year-old from Illinois, wasn’t injured.