The FedEx driver who has been accused of murdering a seven-year-old girl claimed he had reversed his van into her but she was still alive when he put her in his van.
Tanner Lynn Horner, 31, has been charged with murder and aggravated kidnapping after the death of Athena Strand in the town of Paradise, Texas, US.
According to the arrest affidavit released Thursday, Horner told police he put the girl in his work van after he accidentally backed into her.
But he claims she was not seriously injured and that he even spoke to her.
It was only after he "panicked" that "she was going to tell her father about being hit by the FedEx van the defendant was operating", Horner killed the girl, the court documents say.
Athena's mum, Maitlyn Gandy, has said Horner was delivering Athena's Christmas present - 'You Can Be Anything' Barbie dolls - when she was killed.
Breaking down into tears, she said: "Athena was robbed of the opportunity to grow up to be anything she wanted to be.
"I was supposed to bring Athena back home to Oklahoma after Christmas break.
"Now instead, Athena will be cremated and she will come home in an urn because I am not anywhere close to being ready to let my baby go."
Athena's body was found a few miles away from her home, police said.
Investigators determined Horner "had abducted Athena" from her home and believe she died "within an hour or so" of being taken.
Sheriff Akin said he had spent time with the family and that they were "devastated and angry" but grateful for the support of the community at such a devastating time.
He urged the press to "give them the privacy they need".
Sheriff Akin, who has been in law enforcement for 50 years, said this was "one of the toughest investigations" he'd ever been involved in.
"Anytime there's a child that dies, it just hits you in the heart," he said. "You compare that child to your own children when they were that age. It just takes the wind out of your sails."
An Amber Alert was issued on Thursday December 1 for Athena after she vanished the night before.
The 7-year-old was reported missing by her stepmother to the Wise County Sheriff's Office at 6:40pm on Wednesday after the family spent an hour looking for her.
FedEx van are equipped with cameras that capture one minute clips, investigators found.
This was studied and "found the driver had taken a young girl who was visibly similar to Athena in his van. The driver was seen on video talking to her in the van."