A part-time Tennessee model found murdered after disappearing from her home had only been casual friends with her killer for a few weeks, police in Bartlett said Wednesday.

The body of Lisa Renee Davis, 29, was discovered after her attacker committed suicide and left a note with details of the crime.

Austin Agee, 21, had just begun spending time with Davis and her group of friends about two or three weeks ago, police told reporters Wednesday. He was believed to be one of the four people out with Davis the night she vanished.

"Mr. Agee was a friend and acquaintance of Miss Davis," said Bartlett Police Lt. Rory Mack. "She really didn't know him too well." There was no romantic relationship between them, he said.

Agee left a four- or five-line note for detectives after shooting and killing himself at his parents' home, according to Mack.

"He said he was sorry for what he had done, and we would find Lisa's body in a field," he said.

Mack wouldn't discuss the condition of Davis' body, but said she was found with a camouflage jacket draped over her.

Detectives don't know the motive for the killing. Mack said they're analyzing forensics and DNA evidence.

Davis was last seen about 2 a.m. Sunday when friends including Agee dropped her off at home after a night out. Co-workers at a local motorcycle dealership grew worried when she didn't show up to her job there on Sunday and called authorities.

On Tuesday, police named Agee as a person of interest in the case.

Mack said he'd been questioned along with her other friends and had given a similar story about the night Davis disappeared, but his behavior made investigators suspicious.

"He was real nervous," Mack said. "His body language and the way he was acting made detectives think he was hiding something."

Police arrived at Agee's house in Arlington, Tenn., Tuesday evening to question him in the case when they heard gunshots inside. They learned Agee killed himself in the presence of his parents, Thomas and Connie Agee.

The Agees' home was about seven miles from Davis' residence in Bartlett, where police found pools of blood after she didn't come to work Sunday at Bumpus Harley Davidson.

When investigators searched the home Davis owned with her ex-fiance, the woman's car was still there, and her keys, purse and cell phone were inside. There were no signs of forced entry.

Mack said police still aren't sure how Agee got into the house.

Davis' former fiance is a Shelby County Sheriff's deputy. The couple had been separated for two to three weeks, according to police.

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