CHICAGO (CBS) — Federal authorities say a Chicago man sent letters to 16 states that purported to be from Osama bin Laden, and that claimed that al-Qaeda had planted bombs around the country.

Timothy P. O’Donnell, 51, was charged with nine counts of falsely threatening the use of explosives in an indictment returned Thursday.

Prosecutors say there was never any actual danger that O’Donnell was really going to blow anything up, but Chicago FBI Special Agent-in-Charge Robert Grant emphasizes that “there are serious consequences for those who allegedly make false threats.”

Dozens of identical letters went out to addresses in 16 states in March 2011. They claimed to be from bin Laden, and among other things, said al-Qaeda had planted 160 remote-controlled nuclear bombs throughout the country.

The purported bombs were placed in churches, schools, hospitals, financial institutions, and government buildings, the letter claimed.

The indictment accuses O’Donnell of sending the letter between March 18 and 22 of last year from Chicago to two local businesses, as well as recipients in the states of Florida, Idaho, Iowa, Pennsylvania and Tennessee. But these were not the only recipients.

If convicted, O’Donnell could be sentenced to 90 years in prison and face $2.25 million fine.