BOSTON – An Arizona man was sentenced Wednesday to more than one year in prison for threatening to bomb Harvard University and shoot attendees at the school's first-ever black commencement.

Nicholas Zuckerman, 25, was sentenced to 15 months in prison by Boston federal judge Indira Talwani. In a deal with prosecutors, he had pleaded guilty in February to two counts of transmitting in interstate and foreign commerce a threat to injure the person of another.

Zuckerman, who resides in the Phoenix area, was indicted last year for threats made through posts on Harvard University's Instagram page in May 2017 ahead of commencement ceremonies. It came as Harvard was preparing to hold its inaugural Black Commencement, billed as an opportunity to celebrate the accomplishments of black graduates.

Under the username "russian_goalkeeper94," according to prosecutors, Zuckerman posted his first threat on May 13, 2017, on a photo on Harvard's Instagram published two days earlier featuring three black women.

He wrote: "If the blacks only ceremony happens, then I encourage violence and death at it. I'm thinking two automatics with extendo clips. Just so no n----- gets away."

The same day he posted the hashtag "#bombharvard" and wrote "end their pro-black agenda" on a separate Harvard Instagram post that included a photograph depicting the American flag.

Some 10 minutes later, prosecutors say, Zuckerman uploaded the comment "#bombharvard" to other users' posts approximately 11 times over a span of approximately four minutes.

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A citizen who saw the posts alerted Harvard University Police on May 14, and the case was referred to federal authorities.

In court filings, prosecutors say the FBI did not spot Zuckerman in the Cambridge, Massachusetts, area in the days leading up to the May 23 commencement. Authorities did not see him at the event either – nor do they believe he was there – and the commencement took place as planned.

U.S. Attorney Andrew E. Lelling, in a statement, said, "The divisiveness of our public discourse does not excuse making any group of people feel unsafe."

“We will investigate all threats that cross the line of free speech and infringe on the safety and security of members of our community, especially when those threats are based on race or other immutable characteristics.”

Cara McNamara, the public defender who represents Zuckerman, did not return a message seeking comment.

According to prosecutors, Zuckerman was tracked down and interviewed by the FBI at his Phoenix home on November 15, 2017. He initially claimed no memory of the posts and speculated someone might have hacked his account, prosecutors say. But he later admitted to "knowingly and intentionally" posting the threats.

McNamara last week filed a motion, granted by the judge, for the defendant's sentencing memorandum to be filed under seal, keeping Zuckerman's personal information out of the public record.

Prosecutors had recommended that Zuckerman receive between 12 and 18 months of incarceration. He faced a maximum penalty of five years in prison for each count under federal law.

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