NEW YORK – The brother of imprisoned financier Bernard Madoff was sentenced Thursday to 10 years in prison for crimes committed in the shadow of his notorious sibling by a judge who said she disbelieved his claims that he did not know about the epic fraud.

Peter Madoff, 67, had agreed when he pleaded guilty in June to serve the maximum sentence allowable to the charges of conspiracy and falsifying the books and records of an investment adviser. He follows to prison his 74-year-old brother, who is serving a 150-year sentence after admitting he created a fraud so large that thousands of people lost $20 billion.

U.S. District Judge Laura Taylor Swain urged Peter Madoff to tell the truth even now.

The judge said Peter Madoff, wearing a well-tailored charcoal suit, was “frankly not believable” when he claimed at his plea that he only learned of the fraud when his brother revealed it to him just before he surrendered to authorities.

Peter Madoff spoke briefly Thursday and less emotionally than in June, saying: “I am deeply ashamed of my conduct and have tried to atone by pleading guilty and have agreed to forfeit all of my present and future assets.”

He added: “I am profoundly sorry that my failures let many people down, including my loved ones.”

Two investors, among 40 who wrote victim impact statements, spoke during the proceeding.

Investor Michael T. De Vita, 62, also called for truth, saying he believed “it to be physically impossible for a single person to carry out such a gargantuan task all by himself.”

“All of this was preventable if only one person was willing to do the right thing and stop this in its tracks years ago. Peter Madoff could have been that person,” he said.

Amy Luria Nissenbaum, 49, choking up at times, also complained that Peter Madoff had chosen even after his plea to “turn a blind eye.” She said her home was in foreclosure and some days she struggles to “clothe and feed my children.”