A Massachusetts broker and investment advisor has been sentenced to 17 years in federal prison for defrauding rare coin investors out of $7.8 million and other criminal charges, says the Securities and Exchange Commission.

Arnett L. Waters of Milton, Mass., sold coins at prices inflated by an average of 600 percent and convinced coin owners to return the coins to him on the premise he was going to sell them on their behalf. Instead, he sold the coins and kept the proceeds for himself, the SEC says.

He pled guilty to defrauding the coin customers and to 16 other criminal charges of fraud, money laundering and obstruction of justice. The criminal charges were brought by the U.S. Attorney for the District of Massachusetts. Waters was initially fingered by the SEC during a 2012 examination of his securities business by the agency.

He was also sentenced to three years of supervised release and ordered to pay $9,025,691 in restitution and forfeiture. The SEC said that Waters was sentenced Friday.

He pled guilty to using fictitious investment-related partnerships to draw in investors, misappropriate their investment money and spend the vast majority of it on personal and business expenses and debts, the SEC says.  He raised at least $839,000 from at least 13 investors including $500,000 from his church.

Waters operated two companies, a broker-dealer, A.L. Waters Capital, and an investment advisor, Moneta Management LLC.

He also pled guilty to making multiple misrepresentations to the SEC staff. The SEC has barred him from doing any business in the securities industry.