JACKSONVILLE -- The man who authorities say masterminded a scam to use a veterans charity as a front for an illegal gambling operation worth nearly $300 million was a well-known attorney who once ran a marathon in a suit as a publicity stunt.

Jacksonville attorney Kelly Mathis was identified Wednesday by authorities as the man at the center of the alleged racketeering scheme. Two other men charged as co-conspirators had experience running gaming parlors, including Johnny E. Duncan, who was charged more than 20 years ago with creating a fake charity to sponsor bingo gaming, which allowed the games to operate tax-free. The other man, Jerry Bass, had previously worked as general manager of a video poker parlor in South Carolina.

Authorities say Mathis made about $6 million from the operation. During a news conference Wednesday, Florida Attorney General Pam Bondi unveiled a poster with a photo of Mathis, linked to dozens of alleged gambling operations. Officials say he was the registered agent for 112 businesses related to the investigation, which was handled by federal, state and local law enforcement agencies. Nearly 60 people have been arrested so far.

"Kelly Mathis ... appears to be the commonality of those who were arrested," Florida Department of Law Enforcement Commissioner Gerald Bailey said.

The organization under investigation — Allied Veterans of the World — ran more than 40 Internet parlors offering computer games of chance, until this week.

Authorities said the organization’s executives gave precious little to veterans and lavished millions on themselves, spending it on boats, real estate and Maseratis, Ferraris and Porsches.

Bondi called the alleged scam "callous" and "despicable" and said it "insults every American who ever wore a military uniform."

The scandal has led to the resignation of Lt. Gov. Jennifer Carroll, a Republican who once co-owned a public relations firm that worked for Allied Veterans. She has not been charged with any wrongdoing, but she resigned a day after she was questioned by investigators. She said she didn’t want her ties to the organization to be a distraction for Republican Gov. Rick Scott’s administration and that she was cooperating with the probe.

Meanwhile, news reports of the investigation sent shock waves Wednesday through the Jacksonville legal community, in large part because Mathis is a well-known lawyer. The city’s Fraternal Order of Police president and vice president — both police officers — were also caught up in the arrests.

Mathis, 49, is the past president of the Jacksonville Bar Association. He headed the group about six years ago, according to Ray Driver, the current president.

"It’s unfortunate that a member of our profession is swept up in this," Driver said. "I’ve always thought that Kelly was a very nice guy. Very professional."

Unlike membership in the state Bar, which is mandatory for lawyers, the Jacksonville group is voluntary.

Driver said Mathis’ presidency of the group did not overlap with his tenure as Allied Veterans’ registered agent.

A security guard Wednesday turned an Associated Press reporter away at the entrance to the Jacksonville gated community where Mathis lives, 1.5 miles from the exclusive Deerwood Country Club. The attorney’s 7,890-square-foot home on Riding Club Road has five bedrooms and 4 1/2 baths. Duval County records show Mathis bought it in September 2008 for $875,000.