As a dog in war-torn Afghanistan, Target survived an explosion set off by a suicide bomber she had fought off, potentially saving dozens of soldiers' lives. But Target could not survive her time in the care of Pinal County's Animal Control division.

Target, brought to the San Tan Valley area southeast of Phoenix by a soldier who befriended her in Afghanistan, was accidentally euthanized Monday morning.

Previously: 4-legged Afghanistan hero

Her owner, Sgt. Terry Young, found this out after he showed up at the shelter to claim Target, who had slipped out of his back yard over the weekend.

"I just can't believe that something like this would happen to such a good dog," Young said.

Pinal County is investigating what it says appears to be a mistake at its Casa Grande shelter.

"When it comes to euthanizing an animal, there are some clear-cut procedures to follow," Ruth Stalter, the county animal control director, said in a statement. "Based on my preliminary investigation, our employee did not follow those procedures."

A county spokesman said the employee is on paid administrative leave during the investigation into what happened with this dog, which forged a strong friendship with her owner after possibly saving his life.

Young brought Target back to Arizona after the dog, along with two others, frightened a suicide bomber who was trying to detonate himself inside a military base. Target snapped and barked at the bomber. Rather than making it into a building where soldiers were phoning home or exercising, the bomber set off his bomb in a doorway.

Five soldiers were injured, but they and others credited Target and the other dogs with saving their lives. Young figured he would have been fatally injured by shrapnel had Target not intervened.

Young said Target was treated like royalty the rest of her time at the base at Dand Patan, near the Pakistan border.

Young brought Target to his San Tan Valley home in August. The dog's story was featured in The Republic and on "The Oprah Winfrey Show."

On Friday morning, the day after Veterans Day, Young put some breakfast in Target's bowl.

"Seriously, it doesn't matter where she was in the house or outside, as soon as she heard me messing with the package, she would come running," he said.

But there was no Target.

Young went to his back yard and found a gate wide open. He put out online notices and contacted TV stations that did reports on the missing hero dog.

Heather Murphy, a spokeswoman for Pinal County, said a neighbor found Target wandering stray on Friday, put her in his back yard and called the pound. The dog did not have a microchip or tag, Murphy said.

On Friday night, Young found Target's picture on a website used by Pinal County's dog catchers to help owners track lost pets. It was about 6 p.m. and Young figured the shelter was closed for that night and for the weekend.

He was half right. The shelter's hours on Saturday are from 10 a.m. to 2 p.m. Still, Young rested easy. "She's in the pound. At least she's safe," he said.

He showed up at the pound Monday and filled out some forms. Then, he said, a staffer brought out another dog. Young told him that wasn't his dog and showed a picture of Target, who wore a distinctive pink camouflage collar.

An hour passed. Then, Young saw one worker come out from the back sobbing. And the director of the shelter told him there had been a mistake.

Young said his wife and three children, ages 14, 7, and 4, want to see Target's body. He decided to pass, not wanting to remember her that way, he said.

The family will get Target's cremated remains.

"The 4-year-old is really taking it hard right now," Young said. "She's saying we need to get the poison out of her so she can come home. She can't grasp the idea that she's gone."