Some of the worst US mass shootings in recent years

Nov 5, 2009: The Army says 12 people were killed and 31 wounded in a shooting rampage at its Fort Hood base in Texas. Army officials initially said the suspected gunman was among the dead but later said he survived and was hospitalized.

April 3, 2009: A 41-year-old man opened fire at an immigrant community center in Binghamton, New York, killing 11 immigrants and two workers. Jiverly Wong, a Vietnamese immigrant and a former student at the center, killed himself as police rushed to the scene.

March 10, 2009: Michael McLendon, 28, killed 10 people, including his mother, four other relatives and the wife and child of a sheriff's deputyin rural Alabama before committing suicide.