Kaczynski is serving eight life sentences without the possibility of parole at ADX Florence, a supermax prison in Florence, Colorado. Early in his imprisonment, Kaczynski befriended Ramzi Yousef and Timothy McVeigh, the perpetrators of the 1993 World Trade Center bombing and the 1995 Oklahoma City bombing, respectively. The trio discussed religion and politics and formed a friendship which lasted until McVeigh's execution in 2001. In 2012, Kaczynski responded to the Harvard Alumni Association's directory inquiry for the fiftieth reunion of the class of 1962; he listed his occupation as "prisoner" and his eight life sentences as "awards".