POPLAR BLUFF, Mo. -- A Poplar Bluff teen is in critical condition after her father accidentally shot her with a black-powder gun Monday morning inside their home.

Kaitlyn Elise Pullam, 17, was in critical but stable condition in the intensive-care unit Monday night at St. Louis Children's Hospital, said Butler County sheriff's investigator Randle Huddleston.

Butler County deputies learned Pullam had been shot about 11:25 a.m. Monday.

When Butler County Sheriff's Sgt. Brandon Lowe arrived at the Pullam home in the 500 block of County Road 4222, he said he found the teen lying on her bedroom floor and her father, Joe Denton Pullam, performing CPR.

Lowe said the girl was covered in blood, and she had what he described as a severe wound on the right side of her face.

Lowe said Kaitlyn Pullam was taken to Poplar Bluff Regional Medical Center, where she was stabilized before being flown to St. Louis.

Authorities said they believe the girl was standing by the head board of her bed when the bullet came through her bedroom wall. The bullet "actually went in through her right shoulder, then blew up, and shrapnel hit her in the face and chest and then hit the other wall," Lowe said.

The bullet fragmented and went into her lungs, Huddleston said.

As the girl was being seen to by emergency-services personnel, deputies began investigating the scene and talking with family members.

Barbara Pullam, the girl's mother, told officers she had brought home two .50-caliber muzzleloaded guns to her son from a cabin where they had been stored.

"(Joe Pullam) said they had been in a cabin for three years," Huddleston said. "He thought they were unloaded. He picked one of them up, and while handling the firearm, he inadvertently squeezed the trigger, and it went off."

Joe Pullam reported when the gun went off, he "initially thought it was a powder charge, and he said: 'Thank you, it wasn't loaded.' Then, he looked around the living room and saw the hole in the wall," Huddleston said.

Knowing the wall adjoined his daughter's bedroom, Pullam ran in to check on her and immediately began CPR.

When investigator Kelly Thompson said in his report he found what he described as "large" holes in the living room wall, bedroom wall and Kaitlyn Pullam's head board.