A York man has pleaded guilty to stealing millions of dollars in a Ponzi-like scheme to defraud clients of his investment company.

Over the course of eight years, William Bischoff, who ran Genesis Investments Group in Portsmouth, New Hampshire, stole more than $4.2 million from 26 clients, some of whom considered the financial adviser to be a close personal friend, according to a plea agreement filed in a federal court in New Hampshire.

“Through a web of lies and deceit, Mr. Bischoff betrayed [his clients’] trust and used their money to line his own pockets and prop up his failed investments,” Harold Shaw, special agent in charge of the FBI’s Boston division, said in a statement Thursday, after the financial planner waived his right to indictment.

By promising returns far beyond the market norms, Bischoff convinced one person after another to allow him to invest their money in everything from real estate and high yield notes to private equity in a recycling start-up, the court document states.

But in fact, the 76-year-old was using the funds to pay personal expenses and make his own investments and while using new investors’ money to pay other clients, his January plea deal states. From 2009 to 2017, Bischoff continued to solicit new clients and send his current ones bogus account statements that falsely showed that he’d made the promised investments and turned a tidy profit.

He also pleaded guilty to failing to pay federal income tax, depriving the government of nearly $570,000.

In addition to large fines, Bischoff could face up to 48 months in prison for his crimes. But he could serve as little as half that time if he is able to pay $1 million toward restitution before he is sentenced, the plea agreement states.

Bischoff’s case was investigated by the FBI, the Internal Revenue Service and the New Hampshire Bureau of Securities Regulation. He has cooperated with authorities since May 2017, according to his lawyer, public defender Bjorn Lange.

Bischoff is “ashamed that after decades of being a law-abiding and productive member of his community he misused his talents and betrayed people whose trust he had earned,” Lange said. “He is committed to doing whatever he can to put things right.”

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