FORT HOOD, Texas AP – A key U.S. senator said Sunday he would begin an investigation into whether the Army missed signs that the man accused of opening fire at Fort Hood had embraced an increasingly extremist view of Islamic ideology.

Sen. Joe Lieberman’s call for an investigation came a day after classmates who participated in a 2007-2008 master’s program at a military college said they complained to superiors about Maj. Nidal Malik Hasan and what they considered to be his anti-American views, which included his giving a presentation that justified suicide bombing and telling classmates that Islamic law trumped the U.S. Constitution.