Entertainment Tonight.

The puppeteer who voices the Sesame Street character Elmo has been granted a leave of absence from the long-running children's show in the midst of an allegation that he had a past relationship with a 16-year-old boy.

The Sesame Workshop issued a statement Monday saying that it first learned about the allegation against 52-year-old Kevin Clash last June by a then 23-year-old man who claimed to have begun a relationship with Clash when he was 16. Clash has denied the allegation.

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"We took the allegation very seriously and took immediate action," the statement said. "We met with the accuser twice and had repeated communications with him. We met with Kevin, who denied the accusation."

The Sesame Workshop said it conducted its own investigation and found the allegation of underage conduct to be unsubstantiated, but it did determine that Clash violated policy."Although this was a personal relationship unrelated to the workplace, our investigation did reveal that Kevin exercised poor judgment and violated company policy regarding internet usage and he was disciplined.

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The statement said the leave of absence was granted to allow Clash to take actions to protect his reputation from what he calls the "false and defamatory" allegation of underage conduct.

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