(WFLA/NBC) — Authorities in Texas say a FedEx driver has confessed to abducting a 7-year-old girl from her home and killing her.

Wise County Sheriff Lane Akin said Friday night that Tanner Horner, 31, of Lake Worth was arrested in the death of Athena Strand, according to a report by NBC affiliate KXAS.

“It hurts our hearts to know that that child died, so much so that she is on her way now to the medical examiner’s office and there is a Texas Ranger in front of her and a Texas Ranger behind her,” Akin said in a late-night press conference.

Athena was reported missing Wednesday after her family said she vanished from her room. Authorities said the girl’s stepmother looked for her for an hour before calling for help, which triggered an AMBER Alert.

According to KXAS, Athena’s family said she was afraid of the dark and would not have wandered out alone.

For days, law enforcement officers and volunteers searched for Athena. Helicopters with thermal imaging technology were even deployed but could not find the first grader.

Akin said during their search, investigators learned that Horner had made a FedEx delivery to Athena’s home at around the same time she vanished.

“The driver abducted Athena, and from the investigative standpoint, digitally as well as interviews, we think Athena died within just the very hour or so after her departure from her home,” the sheriff said.

James J. Dwyer, acting special agent in charge for the FBI in Dallas, said Horner was located and taken into custody with help from FedEx and digital evidence.

Horner confessed to killing the child, but the sheriff did not say what the content of the confession was.

Akin said Athena’s family has been notified of what happened.

“I spent quite a bit of time with the family,” the sheriff said. “They appreciated the fact that we care so much. They’re devastated. They’re angry because of what happened. A precious child taken from their lives.”

He also said this was one of the hardest cases he had been involved with in his law enforcement career.

Horner has been charged with capital murder for Athena’s death, according to Akin.