Ashley Marie Brotherton, 24, remained in critical condition Monday after a pickup struck her and her longtime boyfriend early New Year's Day, a hospital spokeswoman said.
Police have said Brotherton suffered a traumatic head injury when a red Dodge slammed into the couple as they walked home in downtown Anchorage.
Police on Monday identified the driver of the 1994 Ram 1500 as 21-year-old Tex Daniels II of Chugiak. Daniels has not been charged with a crime and is not in custody, said police spokeswoman Marlene Lammers.
Police say the truck hit the couple from behind near the intersection of West 11th Avenue and I Street.
"A couple of different witnesses indicated they estimated his speed between 50 and 60 miles per hour, and it's a posted 30 mph zone," Lammers said.
Witnesses said the truck was "fishtailing" just before the collision, she said.
Witnesses said the driver tried to leave but couldn't, police said. Two men pulled the driver from the vehicle and held him on the ground until police arrived, according to police.
The collision remains under investigation.
"We're waiting for toxicology (results) and we just want to make sure that he is charged appropriately," Lammers said. "So we are waiting to find out how Ms. Brotherton is doing."
Brotherton's boyfriend, Clayton Tyler Wilbanks, also 24, was in fair condition Monday at Providence Alaska Medical Center, a spokeswoman said.
Brotherton is being treated at Alaska Regional Hospital, where a nursing supervisor said she was in critical condition as of about noon.
Daniels could not be reached for comment. He pleaded no contest to charges of underage drinking in 2007 and 2008, court records show.