Ted Kaczynski, known as the "Unabomber," has been found dead in his prison cell. The cause of death is not yet known, according to The New York Times.
Three people were killed and 23 others were injured by parcel bombs sent to universities and airlines between 1978 and 1995. The streaming service Netflix released a true-crime series about him titled "Manhunt" in 2017. He was convicted in a sensational trial in 1998 and was sentenced to eight life sentences.