ASHEVILLE, N.C. — A 21-year-old who is accused of killing a neighbor and planning to kill up to 1,000 Americans in support of the Islamic State group was sentenced Tuesday morning.

Justin Nojan Sullivan, of Morganton, took a plea deal in November.

He was sentenced Tuesday to life in prison.

Sullivan admitted to attempting to commit an act of terrorism transcending national boundaries.

Investigators said Sullivan admitted planning terrorist attacks, and that he talked to an undercover agent about attacks at a bar or a concert, at places that were “not very far away.” He admitted that he looked online Yellow Pages for places to attack.

Under the plea agreement, prosecutors and defense attorneys agreed that a life sentence is appropriate.

"Justin Sullivan planned to kill hundreds of innocent people. He pledged his support to ISIL and took calculated steps to commit a murderous rampage to prove his allegiance to the terrorist organization," John Strong, special agent in charge of the FBI in North Carolina, said.

Sullivan was arrested at his home in June 2015 after he told an undercover FBI agent that he planned to kill Americans in support of ISIL, according to a news release from the North Carolina U.S. Attorney's Office.

Investigators said an FBI agent contacted Sullivan on June 6, 2015, and Sullivan told him he became a Muslim after he "started thinking about death and stuff." He said he was angry about U.S. airstrikes and planned revenge that would force them to stop.

Sullivan told the agent on June 7, 2015, that he intended get an assault rifle.

Sullivan said to the agent, "Just kill a few people so that I know you are truthful. Just shoot them and leave. Wear a mask. Do it at night." He also said, "I'll kill people this month … I want a car bomb," according to the release.

The agent spoke with Sullivan again on June 8, 2015, and told him they would use homemade silencers on their weapons and would kill 500 people.

The conversation about silencers continued the next day, according to the complaint, and Sullivan corrected his target number. He said, "Five hundred is an incorrect body count for our attack." When asked what the correct number would be, he answered 1,000, and said he was "thinking about using biological weapons."

Sullivan said, "Our attacks need to be as big as possible. We can do minor assassinations before the big attack, for training," the complaint said.

"Our attack will be next month," he said. "I'll be doing shooting of my own before then. I'm excited."

The complaint said Sullivan told the agent he needed the silencer "before the end of next week," an apparent reference to June 19. Click here to continue reading.