Medical examiners were using dental records Saturday to try to determine if two bodies found buried in a wooded area off Interstate 80 are the New Hampshire siblings killed by their father 2 1/2 years ago.

The children's mother, Teri Knight, said she was hopeful authorities had finally found her daughter Sarah, 14, and son Philip, 11.

The children disappeared with their father, Manuel Gehring, in 2003 amid a custody dispute. They were last seen arguing with him at a July Fourth fireworks display in Concord, N.H. Gehring later said he had pulled off a highway that night and shot the children, then drove for hours with their bodies in his van before burying them.

After Gehring was arrested in California, he told investigators he couldn't remember where he had buried the bodies. He gave vague clues that led to repeated searches along a 700-mile stretch of Interstate 80 from Pennsylvania to Nebraska.

"He told the FBI that he doubled back and he turned left and right here and there," David Ruoff, an assistant New Hampshire attorney general, said Saturday. "He just didn't tell us what exit he took."

Gehring strangled himself in prison before he could be tried.

In 2004, the U.S. Geological Survey did a pollen analysis on soil found under Gehring's minivan and near a shovel used to bury the children. It concluded that the soil most likely came from northeastern Ohio. Teri Knight said she and her second husband had searched within five miles of Hudson last summer.

Hudson resident Heidi Mocas took a bouquet on Saturday to the spot where the bodies where found.

"It's a grave site, and to have had two children there very close in age to my own children, I just thought it was absolutely necessary to put some flowers down," said Mocas, the mother of two teens. "If something like that were to happen to my children, I would hope somebody would do something like this for them."