The crash that killed a married couple and at least three of their children after their SUV plunged off a California cliff last week was intentional and not the result of an accident, investigators said.

Greg Baarts, acting assistant chief of the California Highway Patrol’s northern division, said preliminary data obtained from the SUV’s air bag module suggested the vehicle likely came to a stop at a gravel pullout roughly 70 feet away from the cliff before it accelerated and plunged over the edge. That information, as well as the lack of any physical evidence of an accident, such as tire marks, led investigators to believe the crash may have been intentional, Baarts said during a telephone conference call with reporters Sunday evening.

The death of a family that had once captured the world’s attention has left troubling questions about what may have preceded the March 26 crash along the Pacific Coast Highway near Westport, Calif., a small community about 180 miles north of San Francisco. Officials said they have searched the family’s home in Washington state, as well as the couple’s bank and credit card statements and phone records, for any signs of what may have led to their deaths. Baarts said investigators did not find any suicide notes.

Baarts confirmed earlier reports that the SUV’s speedometer was “pinned” at 90 mph when the vehicle was found. That does not mean the vehicle was going at that speed before it plunged, Baarts said, adding that the speedometer could have been “unintentionally manipulated” during recovery efforts.

Investigators on Sunday also raised the possibility that a crime may have been involved, although they did not say who they believe had committed it or what led them to that conclusion.

“In an incident that took place where people perished, we could be looking at a variety of felony crimes to investigate with this,” Baarts said. “We can’t tell you definitively what crime was committed. I don’t think we’re in a position to say exactly what crime that is at this point in time.”

The developments came nearly a week after the crash that killed the two mothers, Jennifer Jean Hart — who was driving — and Sarah Margaret Hart, both 38, and three of their six adopted children. The other three are missing and are feared to be dead.

Capt. Greg Van Patten, a spokesman for the Mendocino County Sheriff’s Office, said investigators believe that all eight family members were in the SUV that day. Van Patten said they do not know yet why the family left their home in Washington and drove more than 500 miles south to Mendocino County in California.

Days earlier, child services officials had begun investigating the Harts for “alleged abuse or neglect.”

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 Monday, the day of the crash, and Tuesday.

“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.”

The Mendocino County Sheriff’s Office said earlier that the family may not have intended to stay away from home for long because many of their belongings, including a pet and some chickens, were still at their home. First responders immediately found the bodies of Jennifer 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 location where the crash occurred is very difficult to search. Tides are strong and unpredictable,” Van Patten said. “The murkiness of the water makes it difficult for anything to be seen. We can’t even get divers in the water.”

The family had lived in a suburb of Portland, Ore., before they moved north across the Columbia River to Woodland, Wash. Authorities said the family left Oregon to escape intense scrutiny that began in 2014. Devonte Hart was photographed sobbing in the arms of a white police officer in Portland, where people had gathered to support protests in Ferguson, Mo., over a grand jury’s decision not to charge police officer Darren Wilson in the shooting of 18-year-old Michael Brown.

The family’s mixed races have fueled 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.

Meanwhile, those who knew the Harts described them as inspiring and devoted parents who had been unfairly subjected to criticism and assumptions about their motives for adopting the children. Friends also said that the couple tried to keep their children insulated from death threats and hateful emails prompted by the viral picture of Devonte.

But their neighbors in Washington said previous incidents involving the Harts’ children have 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 1:30 a.m., 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 years old, was “rattled to the bone.”

Maureen O’Hagan and Julie Tate contributed to this report.

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