Theodore Kaczynski looks around as U.S. Marshals prepare to take him down the steps at the federal courthouse to a waiting vehicle on June 21, 1996, in Helena, Mont. A spokesperson for the Bureau of Prisons told The Associated Press that Kaczynski, known as the “Unabomber,” has died in federal prison. The cause of death was not immediately known. (AP Photo/Elaine Thompson, File)

RALEIGH, N.C. — Ted Kaczynski, “the Unabomber,” was found dead Saturday at a federal prison in North Carolina, according to national media outlets.

Kaczynski was being held at the Federal Correctional Complex, Butner, in Granville County. He was 81 years old.

In 1998, Kaczynski was sentenced to eight consecutive life sentences.

Kaczynski was transferred to Butner from a Supermax prison in Colorado in late 2021. Butner has the Federal Bureau of Prison’s largest medical complex and is known for treating inmates with health problems, The Washington Post previously reported.

From 1978 to 1995, Kaczynski carried out a violent one-man campaign against the industrialization of society and destruction of nature. From a small cabin in Montana, Kaczynski built and mailed bombs targeting dozens of people.

In total, Kaczynski sent 16 bombs. They killed three people and hurt 23 more.

Kaczynski was captured in 1995 after sending The New York Times and The Washington Post a 35,000-word manifesto, demanding they publish it. His brother, David Kaczynski, read the manifesto and compared it with previous letters from Ted.