The man who admitted killing two teen cousins who broke into his rural Little Falls home is an enigma even to some who knew him.

Some see a decent man, one who helped youths and was only trying to protect himself after a series of burglaries. Others see a highly trained U.S. Foreign Service retiree who coldly executed wayward teens instead of calling the Sheriff's Office.

Byron David Smith, 64, has been charged with two counts of murder in the deaths of Nick Brady, 17, and Haile Kifer, 18. The cousins were buried Saturday after a funeral that drew more than 500 people. But the circumstances of their deaths continue to roil this riverfront community that the three called home.

Smith is an Eagle Scout who grew up in Little Falls and volunteered often in Order of the Arrow, a camping fellowship program within the Boy Scout program. He hired high school kids to help around his property, and for awhile let a teenage neighbor's band play in his two-car garage.

Yet a complaint filed in Morrison County portrays a killer who methodically dispatched Brady and Kifer with final shots at close range and left their bodies in his basement workshop for 25 hours.

"We are all stunned," Boy Scout executive David Trehey of the Central Minnesota Council said.

Smith's brother, Bruce Smith of California, said Byron sat behind a desk much of the time during his two decades as a Foreign Service security engineer, ensuring that State Department buildings from Beijing to Berlin were secure from terrorists and spies. He managed up to 50 workers.

"He's a very smart individual," said Bruce Smith, whom Byron summoned to Little Falls from a Thanksgiving holiday in Baltimore just hours after the killing, rather than calling 911.

But questions remain about the circumstances of the killings, including how a man trained to prevent intrusions by terrorists and spies into U.S. embassies had become the victim of multiple break-ins at his property, the last ending in tragedy.

Smith retired in 2006 from his job protecting embassies and consulates, according to a State Department spokesman.

Smith's job duties included conducting technical security assessments of U.S. facilities to protect them from terrorism or technical espionage. The job requires knowledge and training in countersurveillance measures to protect buildings, computers and network-information systems.

Smith had a top-secret clearance, which is issued only after an extensive background check. His assignments included three-year postings in Senegal and Moscow, as well as Berlin, Beijing and Cairo. Some of his overseas posts were in remote locales where personal security risks were high.

Still, his brother says Byron Smith hadn't seen killing in his job and was unprepared for the encounter that played out about noon on Thanksgiving Day, after he heard a window breaking in his upstairs bedroom while working in his basement, Bruce Smith said.

Byron Smith is 5-foot-10 and 190 pounds, but at 64 may have been no match for the athletic 17-year old Brady, Bruce Smith said. Brady had been involved in wrestling, taekwondo, strength and fitness training, his obituary says.

Bruce Smith said his brother, an avid reader who liked woodworking and tinkering with electronics, is single and has no children.

Byron Smith, one of four children, grew up on the west side of Little Falls. His father, Edwin, was a World War II pilot who worked 36 years for Minnesota Power. He died in 1997. His mother, Ida Verina Smith, died in 2009 at age 96.

Byron Smith lives in his late parents' home perched on a riverbank of the Mississippi River, surrounded by pine and birch. Bruce Smith speculates that the Smith house was a target because it's isolated, on eight wooded acres. Last May, county records show, Byron Smith bought an adjacent 10 acres for $277,600.

Lori and Scott Williams, whose property abuts the Smith land, said they were spooked by the man, who often fired guns on his property. They suspected Smith in the disappearance of neighborhood pets, Lori Williams said, and took their concerns to law enforcement. Deputies told her nothing could be done, she said.

Bruce Smith said neither he nor his brother liked dogs because they leave messes.

After six or eight burglaries of his house and garage in the past three or four years, Byron Smith was fed up and frustrated because he thought the sheriff's office wasn't doing enough to solve the break-ins, his brother said.

Sheriff's records show that Smith had reported only one burglary, on Oct. 27, when sentimental items, including his father's hunting shotgun, were among $10,000 in reported losses.

Deputies discovered the bodies of Brady and Kifer on Nov. 23 after Byron Smith called a neighbor, asking about a lawyer and letting the neighbor know that he should call authorities.

In an interview Nov. 25 in the small, tidy house with linoleum floors and turquoise walls, Bruce Smith speculated why his brother didn't call 911:

"He didn't know what to do," the brother said. "He'd never been confronted with shooting somebody."

The complaint charging Byron Smith with two counts of second-degree intentional murder details how he sat down in a chair with a rifle between the killings, minutes apart.

He's quoted as telling police how he shot Brady twice as he came down the stairs, then in the face as the fallen teen looked up at him. Smith dragged Brady's body into his workshop, and out of sight from the top of the stairs.

A few minutes later, Kifer came down the stairs. He shot her, too, but then his rifle jammed. As she lay gasping, he placed a handgun under her chin and fired "a good clean finishing shot" into her cranium, charging documents say.

Minneapolis attorney Steve Meshbesher is representing Byron Smith. He remains in the Morrison County jail in lieu of $1 million bond, or $100,000 cash bail with conditions that include surrendering his passport and turning over firearms to the sheriff.

Joy Powell • 651-925-5038