Ted Kaczynski, the convicted terrorist known by most as the Unabomber, was found dead in his prison cell Saturday morning, according to a spokesperson with the Federal Bureau of Prisons.

The 81-year-old was found unresponsive in his cell around 12:30am and transported to a local hospital where he was pronounced dead.

Kaczynski was previously held in a maximum security prison in Colorado, but had to be moved to a federal prison center in Butner, North Carolina due to his poor health in December of 2021.

Kaczynski went nearly 20 years before he was captured in 1996, and still is considered our country's most prolific bomber.

Between 1978 and 1995, Kaczynski placed or mailed 16 bombs that would kill three people and injure dozens others, authorities reported.

In 1995, before he was identified as the Unabomber, he demanded that newspapers publish the entirety of his manuscript, or the killings would continue. Both the New York Times and Washington Post would publish the 35,000 word manifesto in its entirety at the recommendation of the U.S. Attorney General and FBI.

If it weren't for Kaczynski's brother and sister-in-law, he likely wouldn't have been caught. His sister-in-law, Linda Patrik, was one of the first to identify him after reading the Unabomber manifesto.

Patrik recognized some of the ideas in the manuscript, saying they were similar to letters her husband had received from Kaczynski. They contacted the FBI, who apprehended Kaczynski at his Montana cabin on April 3rd, 1995.

The SWAT team who caught Kaczynski found a live bomb, components, and nearly 40,000 handwritten journal pages including notes from his bomb-making experiments, as well as notes about each bombings.

In 1998, Kaczynski went on trial in Sacramento, California, where the argument was his sanity, and whether he'd be spared from the death penalty. He pleaded guilty to the murders in exchange for life in prison.

The name Unabomber came from the case name UNABOM, a derivative from the targets UNiversity and Airline BOMbing.

Read more at ABC News

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