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Barton Bet Big, Lost Big

Atlanta ground to a halt at midday Wednesday as leaders of the fractious city issued a call for unity and denounced violence in memory of the victims of the worst mass shootings in its history.

"An entire city desperately wants to know why do bad things happen to good people, why no one, including our innocent children, is immune from the evil of violence," Mayor Bill Campbell said during a memorial service at the Peachtree Road United Methodist Church.

Traffic slowed and business stopped in much of Atlanta to mark a moment of silence in honor of the victims.

As Mark Barton's victims were were being mourned, more information was coming to light about the killer's financial life.

In interviews with some of the people who day-traded with Mark Barton, 60 Minutes II learned that Barton, nicknamed "The Rocket" by fellow traders, was a particularly aggressive trader.

According to Harvey Houtkin, the owner of All Tech Investments, where Barton traded, there was one day when Barton made a $106,000 profit. Even by the inflated standards of day trading, this is a lot of money, Houtkin says. There were days, he says, when Barton would stake up to a quarter of a million dollars.

But this daring behavior led to big losses, too. A year after he opened an account at All-Tech, the company forced him to close his account. He had run out of money, Houtkin says.

A few weeks later, Barton opened an account with another day trading firm, Momentum Securities, across the street from All-Tech. Less than two months later, he had lost $105,000 there. His account there was closed July 27.

Later that evening, Barton murdered his wife. That Wednesday morning, he attempted to reopen his Momentum account with a $50,000 check. The office manager refused to accept it. That night, he bludgeoned his two children to death.

Buried on Tuesday were two of the day traders killed Friday, Edward Quinn and Joe Dessert. They were among the nine people killed when Barton opened fire inside two Atlanta brokerages.

He started by killing his wife Leigh Ann at their home. That led to a string of murders that would become Georgia's worst mass killing this century.

Barton's two young children were buried Monday in Lithia Springs: 11-year-old Matthew and 7-year-old Mychelle.

Barton said in a written confession that he killed Matthew, a Boy Scout who played soccer, and Mychelle, who belonged to a Girl Scout Brownie troop, so they would not be left in pain without parents.

"I killed the children to exchange them for five minutes of pain for a lifetime of pain," he said. "I forced myself to do it to keep them from suffering so much later. No mother, no father, no relatives."

On Thursday, the day after the children died, Barton marched into two brokerage firms in Atlanta's Buckhead commercial district and opened fire with two handguns, killing nine people and wounding 13 others. Hours later, he committed suicide when police cornered him at a gas station.

According to his neighbors, Barton was the guy next door who spent his time at home buying Internet stocks. He was a Boy Scout volunteer and seemed to love his children, but now his in-laws and others paint a different picture.

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In 1993 Barton's first wife Debra, and her mother were hacked to death in Alabama. Police said Barton, who was having an affair with his soon to be second wife, Leigh Ann Vandiver, was a suspect although he was never charged.

Vandiver's father said he remained uneasy about his son-in-law because of the 1993 killings. "He never would address his first wife's death with me," he told the Macon Telegraph-Observer. He said his daughter tried to reassure him. "We were reassured, as I guess any child would try to do, that Mark was innocent," he said. "I never bought it."