The accident came at about 5:05 p.m., near the North Birchwood exit. Katherine Ferguson, 32, had been visiting family in Birchwood earlier in the day and was headed home to Eagle River with her children, police say.
A 2000 Ford supercab driven by Ferguson was maneuvering into the left lanes of the highway when it veered into the median. The truck flipped several times down an embankment, police said.
The truck landed on top of 6-year-old John Ferguson, who was partially ejected during the accident, according to police.
Three other children -- an 8-year-old boy and two girls ages 9 and 11 -- were not injured, police said.
Passersby stopped to help and lift the vehicle off the child, who was flown by helicopter to Providence Alaska Medical Center. He was pronounced dead a short time later, police said.
The mother told police that all four children were wearing seat belts, said police spokeswoman Anita Shell. Based on his weight, the 6-year-old "probably should have been in a booster seat," Shell said.
Police are still investigating the crash. No citations have been issued, she said.
The accident temporarily closed inbound and outbound lanes of the Glenn Highway. Inbound -- or southbound -- lanes remained closed for about three hours, police said.
The road was dry with some wet patches, with temperatures at about 30 degrees at the time of the accident, Shell said.
A snowplow on the front of the truck appeared to clip the embankment, causing the vehicle to roll over during the accident, according to police.
The family had been visiting grandparents, Shell said.
Call Kyle Hopkins at 257-4334 or e-mail khopkins@adn.com.
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