COLUMBUS, Ohio — An Ohio man has been indicted on charges that he threatened to blow up the U.S. Supreme Court and attack black men, including a justice on the court, according to an indictment filed in federal court in Cleveland on Wednesday.

David Tuason, 46, targeted black men known to affiliate with white women, well-known white women who had relationships with black men, and children of mixed-race parents, federal authorities said. Tuason sent approximately 200 threats, by mail and e-mail, over the course of 20 years, said acting U.S. Attorney William J. Edwards.

Supreme Court spokeswoman Kathy Arberg confirmed that a threat was made against Clarence Thomas but refused further comment. Thomas is the only black justice on the court.

Edwards said a former Cleveland Cavaliers player and his family members were among those threatened, but he declined to name the player.

According to the indictment, one of the letters refers to an "LN," mentions the Cavaliers and was sent last year to a northeast Ohio high school.

The school is where the daughter of Larry Nance, a former All-Star who played for the Cavaliers and Phoenix Suns, is a student and accomplished athlete.

Attempts to reach Nance for comment late Wednesday were unsuccessful. A call to the Cavaliers, where Nance works, was not immediately returned, and there was no phone number listed for Nance.

Edwards said a well-known black singer who performed at Cleveland's Severance Hall was threatened in a letter sent Feb. 4. The letter was addressed to an "AJ," according to the indictment.

Al Jarreau, the Grammy-award winning jazz and R&B artist, was on the venue's schedule on Feb. 8. He was the only person with those initials listed for January or February shows on the venue's Web site.