The crash happened two months ago near north Highway 1 and Hardy Creek.
A Mendocino County Sheriff's deputy said a local resident reported finding a pair of jeans with a shoe inside one of the pant legs on the ocean beach near the mouth of Hardy Creek. This area is one mile north of the Hart Family crash site.
The jeans were a girl's size 10 regular and the shoe appeared to be a 3.5 U.S. big kid size and/or 5.5 women's U.S. size.
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When Mendocino County officials arrived at the scene, it was determined skeletal remains of what appeared to be a human foot was inside the shoe. A laboratory is being asked to identify the remains through DNA analysis.
The Mendocino County Sheriff's Office Coroner's Division to date has received analysis reports on all of the Hart family members who have been recovered and identified.
The toxicology report showed three of the children had Diphenhydramine in their blood, while one child had no toxicology finding.
At this time the coroner's division is not releasing the names of the children.
During the investigation, officials said the crash may have been intentional.