The Federal Bureau of Prisons reported that terrorist Ted Kaczynski, better known as the "Unabomber," was found unconscious in his cell Saturday morning and later transported to a local hospital, where he was pronounced dead.

Kaczynski was 81 years old and was suffering from several health problems. In fact, this was the reason he was transferred from a maximum security facility in Colorado to a federal medical center in Butner, North Carolina. However, the exact cause of death has not yet been determined.

Who was Kaczynski?

Ted Kaczynski became one of America's most infamous criminals after committing 16 terrorist bombings between 1978 and 1995.

The Chicago-born bomber demonstrated excellent academic abilities from early on. He had a promising career as a mathematician and philosopher after graduating from Harvard University and pursuing a Ph.D. at the University of Michigan. But he chose to live as a hermit in a cabin in Montana and make explosives to attack people he saw as responsible for technological advances that he believed would ruin society.

In 1995 Kaczynski even made a 35,000-word manifesto that was published in the media, in which he railed against the techno-industrial revolution.

"He mentioned problems that we should be concerned about, but, of course, he did it completely incorrectly. He attacked people who were valid researchers," opined Ray Kurzweil, a principal engineer at Google and one of the world's leading AI or artificial intelligence experts.

Because of the attacks, the Unabomber killed three people and injured more than two dozen others. Kaczynski was arrested in 1996 and sentenced to life imprisonment.