The SUV that authorities said was carrying a family of eight - two parents and six adopted children - was traveling at 145km/h before it plunged off a California cliff last week, according to court documents obtained by a local television station.
Fox affiliate KPTV in Oregon reported the SUV's speedometer was "pinned" at that speed, indicating the vehicle remained in motion after it fell and just before it hit the rocks 30m below on the Pacific Coast Highway.
Investigators also did not find any marks showing that the vehicle either accelerated or slowed down before it reached the cliff, or any evidence it crashed into the embankment as it "traversed towards the tidal zone below," according the documents cited by KPTV.
The crash, which killed a family that had once captured the world's attention, has left troubling questions. Killed are the two mothers, Jennifer Jean Hart and Sarah Margaret Hart, both 38, and at least three of their adopted children. The other three remain missing.
The TV report provides a glimpse into what may have preceded the Monday afternoon crash at the ocean overlook near Westport, California, a small community about 290km north of San Francisco. Child services officials in Washington state, where the family lived, also have confirmed they had begun investigating the Harts over "alleged abuse or neglect" days earlier.
The Washington Department of Social and Health Services said it tried unsuccessfully to contact the family on three occasions, first on March 23, three days before the crash, according to a statement. The agency tried again on the day of the crash, and the day after.
"We have not made any findings in this investigation and we had no prior history with this family," the agency said. "We are working with all involved law enforcement agencies on their respective investigations."
Investigators are looking into the possibility of suicide, although police said earlier they have no reason to suspect the crash was intentional. KPTV reported investigators had secured a warrant to search the family's home, including documents such as bank and cellphone records, credit-card statements, journals and suicide notes.
A spokesman for the California Highway Patrol did not respond to a request for comment yesterday. A spokeswoman for the agency's after-hours communications office said the agency was not releasing updates until after the holiday weekend.
The Mendocino County Sheriff's Office said the family might not have intended to stay away from home for long that day because many of their belongings, including a pet and some chickens, were still at their home.
First responders immediately found the bodies of Jean and Sarah Hart and their children Markis, 19, Jeremiah, 14, and Abigail, 14. The others - Devonte, 15, Hannah, 16, and Sierra, 12 - remain unaccounted for.
The family had previously lived in a suburb of Portland, Oregon, before they moved north across the Columbia River to Woodland, Washington. Authorities said the family left Oregon to escape intense scrutiny that began in 2014, when Devonte Hart was photographed sobbing in the arms of a white police officer in Portland, where people had gathered to support protests in Ferguson, Missouri. The demonstration was prompted by a grand jury decision not to charge police officer Darren Wilson in the shooting of 18-year-old Michael Brown in Ferguson.
Devonte and his siblings are black; Jennifer and Sarah Hart white.
The family's mixed races have fuelled suspicion and anger about the crash, reflected in hundreds of comments left on Facebook postings mourning the family. Many of the comments questioned the motives of white women who adopted black children.
Those who knew the Harts described them as inspiring and devoted parents who had been unfairly subjected to criticisms and assumptions about their motives for adopting the children. Friends also said the couple tried to keep their children insulated from death threats and hateful emails prompted by Devonte's viral picture.
But their neighbours in Washington said previous incidents involving the Harts' children had concerned them.
Bruce DeKalb said Devonte regularly came to his home to ask for food and said his parents weren't feeding him. The teen also asked him and his wife to call Child Protective Services, DeKalb said.
Last month, another sibling, Hannah, knocked on his front door at 1.30am, DeKalb said. She was covered in weeds after jumping out of her family's second-story window. DeKalb said the teenager, who was missing some front teeth and who he thought was only 7, was "rattled to the bone."