Results taken from air samples reveal that a body was decomposing in the trunk of a car driven by the mother of missing Florida toddler Caylee Anthony, a local TV station reported.
Detectives with cadaver dogs said in July they detected the smell of human decomposition coming from the trunk of the Pontiac that the mother, Casey Anthony, was driving when police began investigating the dispappearance of her little girl, who was last seen more than two months ago.
The University of Tennessee "Body Farm" conducted the tests on the car's air samples Aug. 10, and on Wednesday their conclusion was released: a human corpse had been decomposing there, according to WESH-2 TV.
Back in July, Caylee's grandmother Cindy Anthony initially made a frantic 911 call to report that her daughter's car smelled like a dead body. She later said the scent just as easily could have been that of rotting pizza.
Casey Anthony, 22, remains a person of interest in her daughter's disappearance on or around June 16. She has pleaded not guilty to charges of child neglect and lying to investigators. She is out on house arrest after posting a $500,000 bond and being released Aug. 21 after a month-long stint in the Orange County Jail.
Caylee was two years old when she vanished; her third birthday was Aug. 9.
The test results are reportedly the first scientific evidence that there was a corpse in Anthony's vehicle.
Anthony has been offered a conditional immunity deal by authorities if she helps with the search, MYFOXOrlando.com reported, but she only has until Thursday to accept the deal, which is contigent upon concrete information that leads to the discovery of Caylee or her remains.
State Attorney's Office spokeswoman Danielle Tavernier confirmed that Anthony had been invited to meet with authorities to "shed light" on the disappearance of her daughter. She declined further comment.
Also Wednesday, news emerged that a policeman was fired for allegedly lying about a rendezvous he had with Anthony.
Anthony Rusciano, a deputy with the Orange County Sheriff's Office, was terminated on the grounds that he wasn't truthful about meeting Anthony at a party, detectives wrote in a memo obtained by MyFOXOrlando.com.
On Tuesday, 400 pages of case documents released by police revealed, among other new details, that Anthony wanted to give Caylee up for adoption before she was born, but her mother Cindy Anthony convinced her not to.
Anthony has maintained that a baby sitter kidnapped her daughter, but police say they don't believe her. She didn't report Caylee missing until about a month after she said she dropped her off at the sitter's apartment.
The Associated Press contributed to this report.