CHICAGO (AP) -- A federal judge has sentenced Dennis Hastert to 15 months in prison in a hush-money case that centered on accusations that the former U.S. House speaker sexually abused at least four students when he was a high school wrestling coach.

Judge Thomas M. Durkin announced the sentence Wednesday. Hastert also must undergo sex offender treatment, two years of supervised release after his time behind bars and a $250,000 fine to go to a crime victims fund.

He pleaded guilty last fall to violating banking law as he sought to pay someone referred to as Individual A $3.5 million to keep sex abuse secret.

Before he sentenced Hastert, Durkin described the 74-year-old Illinois Republican as a "serial child molester," and that "accusing Individual A of extorting you was unconscionable."

He was the nation's longest-serving GOP speaker and was second in the line of succession to the presidency.

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