Valdosta, Georgia (CNN) -- The death of 17-year-oldKendrick Johnson was awful enough for his parents. Then came the doubtsabout investigators' conclusion that it was an accident.

But the discovery thattheir son's body and skull had been stuffed with newspaper before burialadded a horrific new dimension to their anguish and further fueledtheir skepticism of the official findings.

"We have been let downagain," his father, Kenneth Johnson, told CNN. "When we buried Kendrick,we thought we were burying Kendrick, not half of Kendrick."

Kendrick Johnson wasfound dead in a gym at Lowndes County High School in January. Statemedical examiners concluded that the three-sport athlete suffocatedafter getting stuck in a rolled-up gym mat while reaching for a sneaker.

His parents, Kenneth andJacquelyn Johnson, never have bought that explanation. They won a courtorder to have their son's body exhumed and a second autopsy performed inJune.

During an autopsy,internal organs are removed and examined before being returned forburial. But when Dr. Bill Anderson, the private pathologist whoconducted the second autopsy, opened up the teen's remains, the brain,heart, lungs, liver and other viscera were missing. Every organ from thepelvis to the skull was gone.

"I'm not sure at thispoint who did not return the organs to the body," Anderson said. "But Iknow when we got the body, the organs were not there."

Two entities had custodyof Kendrick Johnson's body after his death -- the Georgia Bureau ofInvestigation, which conducted the first autopsy in January; and theHarrington Funeral Home in Valdosta, which handled the teen's embalmingand burial.

GBI spokeswoman SherryLang told CNN that after the autopsy, "the organs were placed inJohnson's body, the body was closed, then the body was released to thefuneral home." That's normal practice, Lang said.

The funeral home wouldnot comment to CNN. But in a letter to the Johnsons' attorney, funeralhome owner Antonio Harrington said his firm never received the teen'sorgans. Harrington wrote that the organs "were destroyed through naturalprocess" due to the position of Kendrick Johnson's body when he died,and "discarded by the prosecutor before the body was sent back toValdosta."

Stuffing a body with oldnewsprint and department-store circulars -- "like he was a garbagecan," as Jacquelyn Johnson put it -- isn't exactly standard practice inforensic pathology or the mortician's trade. Vernie Fountain, thefounder of a Missouri embalming school, called it "not consistent withthe standards of care" in the industry. And Dr. Gregory Schmunk, thepresident of the National Association of Medical Examiners, told CNN, "Ihave never heard of this practice."

Organs are typicallyplaced in plastic bag, which is then put back into the body cavity afteran autopsy, Schmunk told CNN in an e-mail. While individual organs maybe kept back for further testing, he wrote, "This would not amount toall of the organs in any circumstance that I can imagine."

Funeral homes arelicensed by the Georgia Secretary of State's office, which has opened aninvestigation into how Johnson's body was treated, said Jared Thomas, aspokesman for the agency.

Anderson, who was hired by the Johnson family for a second autopsy, found Kendrick Johnson had sustained a blow to the right side of his neckthat was "consistent with inflicted injury." Challenging the stateautopsy's finding of positional asphyxiation, he concluded the teen diedas the result of "unexplained, apparent non-accidental, blunt forcetrauma."

And death scene imagery obtained exclusively by CNNhas led a former FBI agent to question how Johnson died: "I think thisyoung man met with foul play," said Harold Copus, now an Atlanta privateinvestigator.

Lowndes County SheriffChris Prine refused to discuss the matter with CNN, calling Johnson'sdeath a closed case. The U.S. Justice Department announced in Septemberthat it wouldn't open a civil rights investigation into the case.

But federal prosecutorsin south Georgia have met with the family's representatives and areweighing whether to open their own probe, said Michael Moore, the U.S.attorney whose district includes Valdosta.

"This is about gettingto the facts and the truth, and we want the Johnson family and thecommunity of Valdosta to have confidence in the process," Moore said. "Iam cognizant of time, and we continue to move the process along."

Moore urged anyone withinformation about Johnson's death to contact his office. Johnson'sparents have come to believe their son's death was no accident, and themacabre discovery about their son's body has only deepened that belief.

"It's unbearable, justabout," Jacquelyn Johnson said. "The only thing that wakes you up in themorning is to just keep pushing."

CNN's Mary Lynn Ryan contributed to this report.