A 19-year-old woman is dead and two young children are in critical condition after two vehicles collided at about 4:30 a.m. Tuesday on Highway 202 near Ames Lake Road, close to Sammamish, according to Washington State Patrol Trooper Rick Johnson.

The children — a 4 month old and a 2 year old who are believed to be the woman’s children — were taken to Harborview Medical Center, according to the state patrol. Susan Gregg, a spokeswoman for the hospital, said both children were in the intensive care unit in critical condition.

Two vehicles were involved in the crash: a black car and a white pickup. Johnson said it appeared that the woman, Justina Lamphere of Seattle, who was in the black car with the children, was trying to turn around or exit a driveway when her vehicle was struck.

The pickup driver, a 24-year-old Bothell man, had been on his way to work, Johnson said. He was not seriously injured, though he was taken to a local hospital, Johnson said, and he agreed to a voluntary blood draw.

The roadway was closed until shortly after 10 a.m. Wednesday.

Information from the Associated Press is included in this report.