The revelation came in a preliminary hearing in Wilmington for Shkumbin Sherifi - who is accused of plotting to murder witnesses who testified against his older brother Hysen Sherifi.
Hysen Sherifi was sentenced to 45 years earlier this month in what prosecutors described as a conspiracy to attack the Marine base at Quantico, Va., and targets abroad.
Three other men in his Johnston County, North Carolina-based terror cell pled guilty to terrorism charges in 2011, and three more defendants were found guilty at trial. Another defendant still awaits trial, while an eighth suspect remains at large.
According to an affidavit released this week, Hysen Sherifi confided in an informant that he wanted to kill three witnesses who testified against him and a prisoner he believed had stolen from him.
His brother Shkumbin allegedly paid an FBI informant $4,250 in cash toward the first killing.
At Friday's preliminary hearing, FBI agent James Langtry testified that investigators staged "a hit" on one of the witnesses who testified against Hysen Sherifi. They took photos of the man in a shallow grave with fake blood on his chest. They also staged photos of a beheading.
An FBI informant then passed the photos to Shkumbin Sherifi - who then allegedly showed the pictures to his brother in jail January 22 - telling him the hit had been carried out. FBI agents were waiting for Shkumbin when he left the jail.
The FBI has also accused Shkumbin's girlfriend Nevine Aly Elshiekh, a 46-year-old school teacher from Raleigh, of involvement in the plot. Her first appearance is scheduled for Feb. 3.
A judge ordered Shkumbin Sherifi held for trial Friday without bond.
(ABCnews and the Associated Press contributed to this story)