A Romanian man was sentenced on Wednesday to four years in prison for organizing a wave of swatting calls and bomb threats against dozens of U.S. government targets, including members of Congress , cabinet-level officials, federal judges and the heads of federal law-enforcement agencies, according to prosecutors.

Thomasz Szabo, 27, was a prolific participant in a dangerous form of online harassment that has become an increasingly common occupational hazard for public officials across the American political spectrum.

Prosecutors had recommended a prison sentence of nearly five years for Szabo, who pleaded guilty last June to conspiracy and threats charges. U.S. District Judge Amy Berman Jackson in Washington , D.C., also sentenced him to three years of supervised release after his four-year prison term, according to U.S.…