Major shootings in the United States

Virginia Tech April 16, 2007 - A gunman slaughters 32 people and kills himself at Virginia Tech, a university in Blacksburg, Virginia.

Sandy Hook December 14, 2012 - A gunman kills 20 children and six adults and himself at Sandy Hook Elementary School in Newtown, Connecticut.

Columbine April 20, 1999 - Two heavily armed teenagers go on a rampage at Columbine High School in Littleton, Colorado, shooting 12 students and a teacher to death and wounding more than 20 others before taking their own lives.

Immigration centre April 3, 2009 - A Vietnamese immigrant opens fire at an immigrant services centre in Binghamton, New York, killing 13 people and wounding four. He then kills himself.

Fort Hood November 5, 2009 - A gunman opens fire at Fort Hood, a US Army base in Texas, killing 13 people and wounding 32. The gunman, an Army major and psychiatrist, was sentenced to death for the rampage.

Washington Navy Yard September 16, 2013 - A former Navy reservist working as a government contractor kills 12 people at the Washington Navy Yard. The gunman was killed by police.

Colorado movie theatre July 20, 2012 - A masked gunman kills 12 people and wounds 70 when he opens fire on moviegoers at a midnight premiere of the Batman film "The Dark Knight Rises" in Aurora, a Denver suburb. A former graduate student is sentenced to life in prison for the rampage.

Washington, D.C., snipers October 2002 - Two men ambush 13 people, killing 10 of them, in a string of sniper-style shootings that terrorise the Washington area.

Oregon College October 1, 2015 - A gunman bursts into Umpqua Community College in southwest Oregon and opens fire, killing nine people before police shoot him to death.

Charleston church June 17, 2015 - A white supremacist gunman kills nine black churchgoers during a Bible study session at a historic, predominantly black church in Charleston, South Carolina. The suspect is awaiting trial.