PORTLAND, Ore. -- Oregon child welfare officials knew the family in an SUV that plunged off a California cliff had faced a child abuse investigation in another state when it looked into allegations in 2013, according to documents released Monday. Oregon Child Protective Services obtained records from Minnesota prior to investigating Jennifer and Sarah Hart in July 2013, Portland CBS affiliate KOIN-TV reported Monday.

But the agency closed the case with investigators concluding that they were "unable to determine" whether there was abuse in the home, despite some indications of abuse or neglect.

Records obtained by the TV station show the agency found "some indications of child abuse or neglect" but insufficient information to conclude that it occurred.

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California authorities have determined that Jennifer Hart was drunk when she drove her large family off a Northern California cliff last month and they suspect the crash was intentional. They are still trying to determine a motive.

Toxicology results showed Jennifer Hart's wife and several children had large amounts of a drug in their systems that can cause drowsiness.

The crash happened just days after authorities in Washington state - where the family moved last year from Oregon - opened an investigation following allegations the children were being neglected.

A neighbor of the Harts in Woodland, Washington, had filed a complaint with the state, saying the children were apparently being deprived of food as punishment. No one answered when social workers checking on the report knocked on the family's door March 23, days before their SUV was found off a cliff in Mendocino County north of San Francisco.

Long before the crash, Sarah Hart pleaded guilty in 2011 to a domestic assault charge in Minnesota over what she said was a spanking given to one of her children.

Alexandra Argyropoulos previously told The Associated Press that she contacted Oregon child welfare officials in 2013. The former Hart family friend said she "witnessed what I felt to be controlling emotional abuse and cruel punishment" toward the six children.

Oregon child-welfare officials previously declined to disclose any information about the family, citing privacy laws. But records obtained by the TV station show state child-welfare investigators first tried to contact the family on July 19, 2013.

They didn't observe anyone at home and left a card asking the family to contact a caseworker. Three days later, Sarah Hart called the caseworker, saying the family was soon going out of town. She denied that the children were undernourished, KOIN-TV reported.

Documents show that two people whom CPS investigators contacted expressed concern that the Harts limited food for the six children and noted excessive discipline, including having the children lay on the ground in a dark room for between four and seven hours, KOIN-TV reported.

Growth charts provided to investigators showed all but one of the children were below the chart for height and weight though the doctor said there were no concerns for any of the children despite their size.

The bodies of the women and four children have been recovered. Two other Hart children remain missing and the FBI has placed them on its missing persons list. Nonetheless, investigators said they have no evidence indicating the two remaining children are still alive and officials continue to search the ocean and nearby beaches.

The attorney for the biological aunt of three of the six children says the children never should have been taken from their family in Texas, KOIN-TV reported earlier this month.