(CNN) — An autopsy is scheduled Tuesday for a body found near the Northern California site where an SUV plunged off a cliff last month, killing at least five members of a Washington family in what investigators suspect may have been an intentional crash.

But it could take several weeks to determine whether it’s the body of one of three children missing after the crash because lengthy DNA analysis may be needed for identification, the Mendocino County, California Sheriff’s Office says.

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The body of an African-American female was found floating in the Pacific Ocean surf by vacationers on Saturday, nearly two weeks after an SUV carrying at least a majority of the eight-member Hart family plunged off a cliff and onto a rocky shoreline in a remote stretch in Mendocino County, about 180 miles north of San Francisco.

The bodies of Jennifer and Sarah Hart, both 38, were found on March 26, inside their crashed SUV. The bodies of three of their adopted children — Markis, 19; Jeremiah, 14; and Abigail, 14 — were found nearby.

The Harts’ three other adopted children — Hannah, 16; Devonte, 15; and Sierra, 12 — are missing, but investigators have said they believe the whole family was in the SUV at the time of the crash.

Police have said no one in the SUV was wearing a seat belt and that seawater might have swept away the missing children.

The crash came as child protection personnel in Washington state were trying to visit the family after a neighbor says he reported a child’s complaint of mistreatment.

Investigated as a crime

Mendocino County Sheriff Tom Allman has described the crash as “a crime.” The vehicle appears to have left a highway for a dirt turnout, then accelerated on that turnout for about 70 feet until it went off the cliff, authorities said, citing data from the vehicle’s software and air bag module.

No skid marks were seen in the area, officials said.

“I’m to the point where I no longer am calling this an accident,” Allman told HLN last week.

There were no witnesses to help guide police on what happened. The SUV was discovered by a passerby who saw the mangled wreckage at the foot of the cliff.

A family’s troubled history

The family’s history, including allegations of child abuse and an investigation by Child Protective Services of Washington state, provides clues as to why Allman said he is investigating the case as a crime.

The Harts moved to a home in Woodland, Washington, in mid-2017, recalled neighbor Bruce DeKalb, who said he had two sets of disturbing encounters with the children after the move

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“One of the girls came to the door at 1:30 in the morning and said that she needed help and the parents were not treating her properly, and (she) wanted us to protect her,” DeKalb said, describing the first encounter.

“We ended up getting her back to her parents, … and then I went over there the next morning and just checked on things, and everything seemed normal, and we let it go from there.”

Then in March, DeKalb said, Devonte began “coming over asking for food and saying that they were taking meals away from him due to punishment.”

“It started out as one time a day and escalated up to three times a day until a week went by, and we decided that we needed to get professional help,” DeKalb said.

State officials alerted

DeKalb said he called the state’s Child Protective Services office on March 23. Officials arrived just after Jennifer Hart came home from work, but she didn’t answer the door, he said.

Sarah Hart came home soon after that, DeKalb said. By the next morning, the family and its vehicle were gone.

Officials tried to visit the family twice more, on March 26 and 27, but couldn’t make contact, the Washington State Department of Social and Health Services said.

Sarah Hart also had faced allegations of mistreatment in Minnesota, where she and Jennifer lived when the children were adopted about a decade ago from Texas.

In 2010, Sarah Hart pleaded guilty to misdemeanor domestic assault involving one of the children, according to Douglas County court records.

She told police she had spanked the child over the edge of the bathtub because of the child’s behavior. She was sentenced to community service and one year of probation.

Devonte once had been in the public eye. In 2014, the boy garnered national attention when he embraced a white police officer at a time when racially charged protests were being held across the country following a grand jury’s decision not to indict the white Missouri police officer who killed Michael Brown, an unarmed black man.

Devonte helped quell tensions with his sign offering “Free Hugs,” and his photo was shared around the world.

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