A mother was killed and her young son was injured in a crash on Route 1A in Frankfort on Tuesday, police say. The crash also injured a second driver.

Teresa Sirois, 34, of Brooks, was at the wheel when her car crossed the centerline and collided with an oncoming car about 4:45 p.m., said Stephen McCausland, Maine State Police spokesman. Sirois died at the scene.

Her son Damian Sirois, who is 3 years old, was taken to Eastern Maine Medical Center in Bangor with injuries that were not considered life threatening, McCausland said in a news release. The child was secured in a car seat at the time of the crash.

The driver of the other car, Randall Pukay, 53, of Bucksport, also was injured and taken to EMMC.

State police are trying to determine why Sirois’ car went into the other lane.

Frankfort is in Waldo County.