The highway was closed from its intersection with the Seward Highway west to milepost 70, according to the Department of Transportation website.
Troopers spokeswoman Megan Peters said the highway could open by 6 a.m. today.
"If everything goes smoothly, it could open earlier," she said.
The first crash came at about 5:20 p.m. when a Jeep collided with a motorcycle at Mile 64 of the Sterling Highway, Peters said. Two people on board the motorcycle were killed, she said.
A third person died in a second crash that came roughly an hour to 90 minutes later, at about Mile 45 of the Sterling, Peters said.
The person killed was a passenger in an SUV, Peters said. Details were still emerging from the scene of that accident. Three people injured in that crash were medevaced.
The troopers spokeswoman had little information about the accidents at press time. With two serious accidents along the highway in quick succession, authorities were unable to divert traffic and were forced to close the roadway, she said.
Email Kyle Hopkins at khopkins@adn.com.
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