The Missouri State Highway Patrol says a passenger vehicle hit a tractor-trailer that had slowed down on the highway. The driver and passenger in the car were declared dead at the scene.
The accident happened shortly after 11 a.m. in the westbound lanes of US-36 near 112 Road Southeast.
An investigation continues. The victims were identified as Jason Musser, 26, of St Joseph, and his daughter Charlene Musser, who was five years old.