LOUISVILLE, Ky. (WDRB) -- Officials are investigating what is thought to be one of the largest money fraud schemes in Indiana's history, with at least $110 million stolen, swindled out of a small building in New Albany.

"It was a scam of selling securities, or ownership in oil drilling companies, and in most cases, the companies never really existed," said Floyd County Prosecutor Keith Henderson. "It was only on paper."

We first reported on the scam in March of 2015. Henderson now says it's more far-reaching than he thought. Currently, 15 people have been charged, and 150 victims have come forward from all over the country.

"At one point, an investigator told me we're past the millions stage -- we may be getting into the 'B' for 'billion' -- and that was very sobering in terms of how large it was," Henderson said.

This week, 65-year-old Richard Collins of Charlestown was arrested. He's identified in court records as the "closer." 

Indiana Securities Commissioner Alex Glass says the group claimed to work out of a New Albany building for Earth Energy Exploration, Inc. 

"They bought a list of potential investors -- hired cold callers and the cold callers would call the investor," Glass said.

Henderson said the group tricked people from all backgrounds.

"You know average people, mostly retired, who had nest eggs who were looking for an investment in this low interest rate of return environment," Henderson said.

Collins was booked with 14 others in 2015, but the new charges represent another victim coming forward, saying he paid Collins $12,500. It's on the low end of the scam. Records show some lost six figures. 

"Unfortunately, this isn't the first and it won't be the last," Glass said.

Reports say David Rose, already convicted in a 2009 fraud case, is among the masterminds of the investment scheme. Three other suspects -- David Brown, Brent Lovall and Keith Mohney -- took a plea deal.

Some will avoid prison altogether by testifying for the state. 

"We're going to do our best to hold these individuals accountable," Henderson said.

While most of the victims of this scheme are not in Indiana or Kentucky, local officials want it to serve as a warning: Before you invest, check with the Secretary of State's office in your state to make sure you are working with a licensed company and securities broker.

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