The FBI says a South Carolina man was arrested as he tried to get on a plane to the Middle East to go and fight for the Islamic State told an undercover agent he wanted to torture an American.
A grand jury indicted Zakaryia Abdin on Tuesday on a charge of providing material support to a terrorist organization.
A sworn statement from the FBI says the 18-year-old man talked on social media to what he thought was an Islamic State recruiter but was an undercover agent.
The FBI says Abdin praised the man who killed 49 people last year in a terror attack at a Florida nightclub, suggesting he could also attack a U.S. site.
Abdin was arrested March 30.
Court records did not list an attorney.
The Associated Press contributed to this article.