Fryeburg police continue to investigate a weekend crash that critically injured a pregnant woman and her 8-year-old son.

Police Chief Joshua Potvin said investigators returned Monday to the scene on Route 302 and that charges will likely be filed in connection with the crash.

Potvin said 29-year-old Bridgette McAvoy of Denmark was driving her Subaru Outback westbound on Route 302 around 9:30 a.m. Saturday when a Volvo operated by 56-year-old Irene Thurston of Fryeburg crossed the centerline and slammed into the Subaru.

McAvoy and her 8-year-old son were taken to Maine Medical Center with potentially life-threatening injuries and were initially listed in critical condition. They were in stable/fair condition Monday, Potvin said. McAvoy’s other children, ages 3 and 5, were treated at the hospital and released to family.

Thurston was not injured in the crash. Potvin said Saturday that he believes distracted driving caused the crash.

“Blood was drawn from both operators as is standard protocol during a serious injury crash,” Potvin said in a statement. “We still have a lot of follow-up work to do in this investigation. No charges have been filed but are highly probable in the near future.”

Route 302 was shut down for about 3½ hours while emergency workers attended to the scene and police worked to reconstruct the crash.

This story will be updated.