Military prosecutors will seek the death penalty for Maj. Nidal Malik Hasan, the accused gunman in the Fort Hood shootings who faces 13 counts of premeditated murder. (The last active duty serviceman to be executed was hanged at Fort Leavenworth, Kansas, in 1961.) Hasan will be tried in a military court, instead of a civilian one, reflecting investigators’ belief that he acted alone, despite emails to a radical Muslim cleric. Prosecutors may also file additional charges against the alleged shooter, whose troubled military career has been the subject of intense scrutiny since he emerged as the chief suspect in the aftermath of last week's killings. The major, a psychiatrist, is said to have been a troubled man who flirted with radical Islam and worried his superiors at Walter Reed Medical Center.