FedEx Driver Claims He Struck Athena Strand with Truck, Then Panicked in Fear She'd Tell Her Dad

Tanner Horner, 31, allegedly told investigators he strangled the 7-year-old girl in the back of his van

Athena Strand. Photo: Texas EquuSearch Facebook

A contract driver delivering packages for Fed Ex accused of kidnapping and killing Texas girl Athena Strand along his route claims he panicked after accidentally hitting the child with his van, according to an arrest affidavit reviewed by PEOPLE.

Wise County authorities allege Tanner Horner, 31, said he put Athena, 7, in his van on Nov. 30 after accidentally striking her with the vehicle while backing up. He then allegedly told police he killed the girl inside his van after panicking about what to do next, the affidavit says.

Surveillance footage from inside the van shows Horner talking to a little girl who resembled Athena, per the affidavit.

Horner allegedly told investigators Athena wasn't seriously injured after he struck her — she was speaking and told him her name. However, he allegedly decided to kill her, he told investigators, after becoming afraid she would tell her father he'd hit her with the truck.

At that point, Horner allegedly told authorities, he tried to break Athena's neck, and, when that didn't work, opted to strangle her in the back of the van "with his bare hands," the affidavit states.

Athena was found dead on Dec. 2, dumped in an area near a river in Boyd about nine miles from her home in Paradise. Horner allegedly told authorities where to find her body, the affidavit states.

Shortly before the alleged slaying, Athena — who was staying with her father and stepmother — reportedly got in an argument with her stepmom, Elizabeth Strand, at their house. The stepmom later went to look for Athena, but told authorities she hadn't realized the child had gone outside, most likely to go to her makeshift bedroom. (Athena and her stepsister were reportedly sleeping in a converted storage shed next to the house while the home was under construction, the affidavit states.)

Horner was a contract delivery driver for Topspin, which delivered packages for FedEx. When he saw Athena in the driveway, he had just delivered a package to her home. It was a Christmas gift of "You Can Be Anything" Barbie dolls, said Maitland Gandy, the little girl's mother, during a Thursday press conference.

"I was robbed of watching [Athena] grow up by a man that everyone was supposed to be able to trust to do just one simple task: deliver a Christmas present and leave," Gandy said at the press conference. "I was supposed to bring her back home to [my house in] Oklahoma after Christmas break. Instead ... she will come home in an urn."

Want to keep up with the latest crime coverage? Sign up for PEOPLE's free True Crime newsletter for breaking crime news, ongoing trial coverage and details of intriguing unsolved cases.

Gandy's lawyer, Benson Varghese, also spoke. "Our ultimate goal is to ensure no other parent or grandparent feels the loss Maitland is going through right now," he said. "We are leaving no stone unturned in looking at all the decisions that happened before this tragedy occurred."

Horner is charged with capital murder and aggravated kidnapping in Athena's death. His bond is set at $1.5 million. It was unclear if he has entered a plea or retained an attorney to comment on his behalf.

On Thursday, the District Attorney's office announced it was seeking the death penalty in this case.

* With reporting by Tristan Balagtas