Convicted Fort Hood shooter Nidal Hasan has written a chilling letter to the head of ISIS, also known as the Islamic State, asking to become a "citizen" of the extremist group.
In the undated letter obtained by Fox News, Hasan — the former U.S. Army psychiatrist who fatally shot 13 people and injured dozens more at Fort Hood, Texas, in 2009 — wrote of his desire to join the caliphate from his federal prison cell.
"I formally and humbly request to be made a citizen of the Islamic State. It would be an honor for any believer to be an obedient citizen soldier to a people and its leader who don't compromise the religion of All-Mighty Allah to get along with the disbelievers."
Hasan's attorney told the outlet the letter "underscores how much of his life, actions and mental thought process are driven by religious zeal."
News of the message comes just days after two Americans reportedly died fighting for ISIS in Syria.
U.S. security officials said Monday Douglas McArthur McCain, a 33-year-old from Minnesota, had been killed fighting alongside ISIS militants operating in Iraq and Syria over the weekend. (Video via CBS)
And late Wednesday, sources told KMSP 29-year-old Abdirahmaan Muhumed was killed in the same fight. He reportedly knew McCain from high school. The U.S. has yet to publicly confirm his death.
And U.S. intelligence and law enforcement agencies have reportedly identified almost a dozen other Americans who have traveled to Syria to fight for ISIS. (Video via Euronews)
A senior American official told The New York Times part of the reason ISIS is so appealing is because it has seized territory that it rules by strict Islamic law.
"ISIS is able to hold itself up as the true jihad. They're saying: 'Look at what we are doing, what we're accomplishing. We're the new face. We're not just talking about it. We're doing it.'"
As for Hasan, he was sentenced to death for his crimes almost a year ago. The 2009 Fort Hood shooting has been dubbed the worst mass murder at a military installation in U.S. history.