An Ohio man has been indicted on charges that he threatened to blow up the U.S. Supreme Court building and attack well-known black men, including an associate justice of the court, according to an indictment filed Wednesday.

David Tuason targeted black males known to affiliate with white females, well-known white women who had relationships with black men, and children of mixed-race parents, federal authorities said.

FBI spokesman Scott Wilson said Tuason sent communications as far back as 20 years, Wilson said.

Wilson declined to name those targeted, citing privacy issues. Associate Justice Clarence Thomas is the only black justice sitting on the U.S. Supreme Court.

Supreme Court spokeswoman Kathy Arberg confirmed that a threat was made against Thomas but refused further comment.

Wilson would not confirm that the U.S. Supreme Court building in Washington, D.C., was targeted, but said threats were sent to places where the targets worked or may have attended functions.

"It's been a very long, enduring case," Wilson said. "Basically it's a case we never gave up on."
Tuason, of Pepper Pike, Ohio, was indicted on two counts of transmitting threatening interstate communications and six counts of mailing threatening communications. The indictment was filed in the U.S. District Court for the Northern District of Ohio in Cleveland.

He is in the custody of U.S. Marshals. Each interstate communication charge carries a penalty of up to 10 year in prison and each mail charge carries a penalty of up to five years.

"As far as we know, it's a one-man operation," Wilson said.

Wilson would not specify whether Tuason attempted to carry out the threatened attacks. The threats began in Cleveland and branched out across the nation, Wilson said.