CHATTANOOGA (WRCB) -- If Robert Hardnett's Facebook postings are accurate, he was more than twice the age of his wife Elizabeth when they married almost two decades ago.

At most, she would have been 16 years old.

But this Valentine's Day, Hardnett is in the Hamilton County Jail.

"He just walked into the jail; told them he'd murdered his wife," Chattanooga Police Public Information Officer Nathan Hartwig says. "We took it from there."

'There' led to Power Supply, Inc., on Daisy Street, early Monday evening. Hardnett works there as a truck driver.

"They found her inside the building," Ofc. Hartwig says. "She appeared to have been shot four to six times, and she was dead on the scene."

Investigators believe Elizabeth Hardnett was killed inside the warehouse, after hours. They've recovered a handgun they believe fired the bullets that killed her.

"I can't get into motive, or his intentions, right now," Ofc. Hartwig says.

The Hardnett's Facebook pages offer only hints.

Robert Hardnett's Bio speaks of his "wonderful family of four kids and a loving wife Elizabeth of 18 years."

He has posted several pictures of himself with his wife, smiling.

But both list their status as 'separated.'

Valentine's Day morning, Eyewitness News visited the house in the Woodmore subdivision, listed as Robert Hardnett's home address.

Knocks produced no answer. Neighbors confirm the that Hardnett's nephew lives there. They recognized Robert Hardnett, but not Elizabeth.

A visit to another listed address, near the UT Chattanooga campus, gleans even fewer results.

Hartwig confirms that Tennessee's Department of Children's Services is "involved", but offers no specifics as to whether the couple's children are with family, or in state custody.

"Our child abuse investigators are involved," he says. "That isn't to say we've heard any allegations of abuse."

Court records, however, indicate that Elizabeth Hardnett had been charged with child neglect in December 2010. The record is scant; but says that the District Attorney General's Office dropped the charges.

Robert Hardnett's record bordered on spotless; two traffic and equipment citations in the past fifteen years, both work-related.

He now faces charges of criminal homicide.

The couple's daughter, Janniece, tells Eyewitness News that she's staying with cousins. She's not confirmed the status of her siblings.

Hardnett's Facebook page points to a competitive streak; particularly in athletics.

He lists his avocation as 'tennis instructor for twenty years.' His photo albums include pictures of professional players Rafael Nadal and Roger Federer.

His personal credo: "I will persist until I succeed. I will play my best at all times. I will do my best under any and all circumstances."

"I will not be tempted of anger when losing a point. Instead I will try much harder to win the next. I will persist until I succeed."

Hardnett is confined in isolation, according to jail authorities. He is being watched "very closely."

His first date in court is February 21.

Elizabeth Hardnett's body awaits an autopsy Wednesday.