MINNEAPOLIS (WCCO/AP) — The first guilty plea has come following charges against 60 people in a widespread telemarketing scam that authorities say, overall, bilked more than 150,000 elderly and vulnerable people nationwide of $300 million.

Brian James Williams, 51, was the first to plea guilty in what Minnesota U.S. Attorney Erica MacDonald called the largest elder fraud scheme in the country.

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Williams owned and operated several of the companies involved in the scheme, including Readers Beach Readers Club in San Diego. His companies ran telemarketing call centers in San Diego and St. Paul, MacDonald says.

His companies accounted for fraudulent charges totaling more than $29 million, she added.

Williams agreed to pay that same amount in restitution. He faces a sentence of up to 30 years in prison.

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Court documents say that over the last 20 years, the 60 individuals involved in the scheme used a network of fake magazine sales companies and telemarketing call centers to trick people into making large or repeat payments. Prosecutors worked with the FBI and postal inspection service to bust what they say was a scheme, charging seniors around the country for magazines they never got and then selling their information.

“The resulting numbers are staggering — $300 million pilfered from the bank accounts of mostly older Americans who fell victim to these aggressive telemarketing schemes,” FBI special agent in charge Michael Paul said.

Prosecutors say the companies operated in Minnesota, Florida, Georgia, Mississippi, California, Iowa, Kansas, Missouri, Illinois, Colorado, Arizona, New Mexico, North Carolina, and Arkansas.

The advice from investigators if you are a senior, or have a senior in your life, is to check your finances to make sure. Anyone who believes they may be victims should contact the FBI.

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