Updated

The bond for the mother of missing Florida toddler Caylee Anthony will most likely be revoked, sending her right back to jail, FOX News has learned.

Celebrity bounty hunter Leonard Padilla told FOX that it looks like the $500,000 bond he and his nephew put up to bail 22-year-old Casey Anthony out of jail last week will be revoked, and she will be heading back to jail on Saturday.

The star of the National Geographic reality show "Bounty Hunters" flew in from California with his bail bondsman nephew Tony Padilla to post the hefty bond.

He told FOX that the primary reason to revoke it would be for Anthony's safety. Threats against her and her family have spiked since some preliminary test results reportedly showed evidence of a body in her car, he said.

Anthony hasn't been communicating since her release, he said — which was also factoring in to the talks.

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On Wednesday, results taken from air samples were released, indicating that a body was decaying in Anthony's car trunk. Another round of tests have been ordered, according to MyFOXOrlando.com.

Detectives with cadaver dogs said in July they detected the smell of human decomposition coming from the trunk of the Pontiac Anthony was driving when police began investigating the disappearance 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.

Caylee's grandmother Cindy Anthony made a frantic 911 call in July 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.

The sheriff's office declined comment.

"As has been our policy ... we will not discuss the investigative details pertaining to the Caylee Anthony case to include the results of any evidence submitted for laboratory analysis," Capt. Angelo Nieves said Wednesday afternoon.

Anthony's lawyer Jose Baez claimed he didn't know anything about the results or whether they were based on actual evidence.

Late Wednesday night, the Orange County Sheriff's Office issued a statement confirming that FBI test results are back and would be analyzed and shared with the state's attorney on Thursday, according to MyFOXOrlando.com.

Casey Anthony remains a person of interest in her daughter's disappearance. She has pleaded not guilty to charges of child neglect and lying to investigators.

She is out on house arrest since her Aug. 21 release, which came after a month-long stint in the Orange County Jail.

Caylee was two years old when she vanished. Her third birthday was earlier this month.

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 agreement, which is contingent 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, but MyFOXOrlando.com reported that Anthony did meet secretly with state's attorney representatives.

Also Wednesday, news emerged that an Orange County policeman was fired for allegedly lying about a rendezvous he had with Anthony.

Deputy Anthony Rusciano was terminated on the grounds that he wasn't truthful about meeting Anthony at a party, according to an internal memo.

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.

Click here for a timeline of the case.

Click here for more on this story from MyFOXOrlando.com.