LOS ANGELES (CBSLA) — A Twentynine Palms man has been sentenced to a year and a day in federal prison for making more than 10,000 harassing phone calls to government offices and threatening to injure the congressional staffers who answered.

Robert Eric Stahlnecker, 48, was sentenced Thursday after a two-trial in February found him guilty of one count of making threats by interstate commerce and five counts of anonymous telecommunications harassment. He was acquitted of two counts of threatening federal employees.

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Stahlnecker was found to have made eight calls within seven minutes to the Washington D.C. office of Sen. Sherrod Brown of Ohio, berating the intern who answered, insulting her with vulgar language and threatening to come to the senator’s office to kill her. Prosecutors showed that he made multiple abusive phone calls to staff members and interns of multiple members of Congress between September and November 2019.

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He made more than 10,000 calls to government agencies and elected officials between January and November of last year, with 3,600 calls to the Veterans Affairs complaint line and 2,500 calls to the United States senators from California, according to the Department of Justice.

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Stahlnecker has been in federal custody since his arrest in December.