Ted Kaczynski, known as the Unabomber, died by suicide in his prison cell, according to a 911 call obtained by TMZ. The 81-year-old was found dead in a federal prison medical center Saturday morning, prompting an official to call emergency services. Enough time had passed for rigor mortis to set in, TMZ reported. He was serving four life sentences after killing three people and injuring dozens more in a series of 16 bombings spanning nearly two decades. Other reports confirm the Unabomber died by suicide, but the official cause of death has yet to be released awaiting the autopsy results. Months before his trial in 1998, Kaczynski reportedly made a similar attempt and was placed on suicide watch.

If you or a loved one are struggling with suicidal thoughts, please reach out to the National Suicide Prevention Lifeline at 1-800-273-TALK (8255), or contact the Crisis Text Line by texting TALK to 741741. You can also text or dial 988.