An investigation is underway after a 3-year-old was killed and a 2-year-old was critically injured in a head-on collision on Thursday evening in Macomb County, Michigan.

According to Michigan State Police, the Macomb County Dispatch received calls at about 5:20 p.m. about the crash on M-53 and Ebeling Road in Bruce Township. Troopers who responded to the scene found two vehicles, one of which carried a male driver, hia 3-year-old daughter and 2-year-old son. An 18-year-old woman from Davison was in the second vehicle.

A preliminary investigation revealed that the man was driving in a 2011 Chevy Impala with his two children on southbound M-53 when he crossed over into the northbound lanes and collided with the 18-year-old, who was driving a 2023 Chevy Impala.

MSP says the 3-year-old girl was pronounced dead at the scene, and the 2-year-old boy was taken to a hospital with life-threatening injuries. The male driver and the 18-year-old woman were also transported to a hospital with life-threatening injuries.

Police say the 18-year-old was driving behind her boyfriend before the crash. The boyfriend was able to swerve out of the way and avoid being struck.

The cause of the crash is under investigation. MSP says there's no evidence suggesting that the male driver in the 2011 Chevy used brakes before colliding.

MSP First Lieutenant Mike Shaw says neither child was restrained properly at the time of the crash, and there was one car seat in the vehicle.

"What we don't know is why the at-fault driver crossed over into the oncoming lanes. A blood draw was taken as part of the investigation," Shaw said in a statement. "It is particularly heartbreaking when a preventable crash occurs on a holiday. It is even worse when a child loses their life. Please make sure to wear your seatbelt and that your children are properly restrained every trip."