Nidal Hasan, Ft. Hood shooting suspect
Fort Hood shooter Nidal Malik Hasan has written a letter, saying he wants to join the Islamic State. Reuters

U.S. Army Maj. Nidal Hasan was convicted Friday on all 13 counts of premeditated murder charges and 32 attempted premeditated murder charges he was faced with for the mass shooting at Fort Hood, Texas.

A jury of Army officers convicted Hasan, an American-born Muslim, during his court martial at Fort Hood for the November 2009 massacre. Hasan faces the death penalty when the penalty phase of his court martial begins Monday. Whether Hasan gets death will be up to a military judge.

Hasan, who acted as his own attorney, admitted to killing 13 people when he gave his opening statement at the court martial. The Army psychiatrist joined the military in 1998 but testified that he sympathized with al-Qaeda, which inspired him to go on the Fort Hood shooting rampage.

The Fort Hood killings were the largest mass murder at an American military facility in U.S. history.