Police in the eastern U.S. state of New Jersey arrested a man early Monday on terrorism charges, accusing him of conspiring to support the Islamic State.
Alaa Saadeh, 23, was one of four people identified in a sting operation on a group planning to travel to join the militants, according to the FBI.
Federal agents were investigating Saadeh, his brother, and two other men in the New York and New Jersey area, after an informant who had lived with the brothers tipped off federal agents in April, the Department of Justice revealed.
An affidavit from an FBI official details the allegation that Saadeh purchased an airline ticket from New York to Amman for his 20-year-old brother to travel to join IS militants on May 5, 2015.
The two other men were arrested separately earlier in June.
By the informant's account, the Saadeh brothers increasingly voiced support for IS actions, including the militants' highly-publicized killings.
If convicted of three applicable federal charges, Alaa Saadeh faces a maximum of 20 years in prison on each count and a fine of $250,000.