A convicted terrorist who plotted to kill three FBI agents as revenge for his conviction was sentenced to life in prison on Monday.

Hysen Sherifi, 29, received the sentence from U.S. Attorney District Court Judge W. Earl Britt. His 23-year-old brother, Shkumbin Sherifi, and Nevine Aly Elshiekh, 48, were sentenced to 36 months and 42 months respectively for aiding the plot.

A jury found Sherifi guilty on Nov. 8 of planning an attack on a U.S. Marine Corps base in Quantico, Va. as part of a violent jihad. Sherifi was a member of a Raleigh, N.C., jihad group led by Daniel Patrick Boyd. Sherifi was charged with plotting to kill six witnesses who testified against him during his 2011 trial.

While awaiting sentencing after his October 2011 conviction, Sherifi plotted to kill three FBI agents and three government informants who testified at his terrorism trial. Sherifi sought to kill these individuals as revenge for his conviction; to prevent their testimony at co-conspirator Anes Subasic's upcoming trial; and to get a new trial for himself, according to the FBI.

Sherifi recruited his brother, Shkubmin Sherifi, and Nevine Elshiekh, a local school teacher. The Sherifis and Elshiekh then raised money to pay for the murders.

In January 2012, Elshiekh met with a government informant whom she believed to be the middleman for a hit man in order to discuss the murder plot and possible targets. Elshiekh then relayed that information to Sherifi during a jail visit. Sherifi specified that he wanted each target to be beheaded and photographed after the beheading.

At a second meeting, Elshiekh confirmed the identity of a government witness to be murdered and made a down payment. The conspirators then worked together to collect the remaining funds needed to pay for the first murder. After collecting the funds, the conspirators arranged another series of meetings with the witness to pay for the murder and get photographic confirmation of the first murder.

On Jan. 22, 2012, the conspirators were arrested shortly after Shkubmin Sherifi accepted pictures purporting to show a beheaded government witness. On Feb. 21, 2012, a nine-count indictment was filed charging Sherifi, Shkubmin Sherifi, and Elshiekh.