Here's an edited list of mass shootings in the United States:
May 18, 2018: At least 10 people were killed in an active shooter situation at Santa Fe High School in Santa Fe, Texas.
Feb. 14, 2018: A former student who had been expelled for disciplinary problems is arrested after a shooting at a Florida high school that left 17 people dead and 16 wounded.
Oct. 1, 2017: Gunman opens fire on a country music concert in Las Vegas, Nevada, killing at least 58 people and wounding more than 500 others, in the deadliest mass shooting in modern U.S. history.
June 2016: Gunman kills 49 people at Pulse, a gay nightclub in Orlando, Florida.
FILE - People hold candles during a vigil downtown for the victims of a mass shooting at the Pulse nightclub in Orlando, Florida, June 13, 2016.
December 2015: Couple kills 14 people after storming California social services agency. They are killed in gun battle with police.
November 2015: Gunman kills three after storming a Colorado Planned Parenthood clinic; he is arrested after a hourslong standoff with police.
October 2015: Gunman kills nine at an Oregon community college before killing himself after a gun battle with police.
July 2015: Gunman kills five at U.S. Navy Reserve center in Tennessee before being shot and killed by police.
June 2015: Gunman kills nine people in South Carolina church before fleeing, is captured the following day. The gunman, Dylann Roof, was sentenced to death.
FILE - Mourners pass by a make-shift memorial on the sidewalk of in front of the Emanuel AME Church following a shooting in Charleston, S.C., June 18, 2015.
May 2015: Nine killed in shootout between rival motorcycle clubs and police at Texas restaurant.
October 2014: Teenage gunman kills four teens, two of whom are his cousins, in Washington state high school before committing suicide.
September 2013: Gunman kills 12 people at a naval facility in Washington before dying in a gun battle with police.
FILE - A makeshift memorial with crosses for the victims of the Sandy Hook Elementary School shooting massacre stands outside a home in Newtown, Conn., on the one-year anniversary of the shootings, Dec. 14, 2013.
December 2012: Gunman kills 26 adults and children at Sandy Hook Elementary School in Connecticut before killing himself.
August 2012: Gunman kills six people at Sikh Temple in Wisconsin before committing suicide after being shot by police.
July 2012: Gunman kills 12 people during showing of a “Batman” movie in Colorado.
January 2011: Gunman kills six people and wounds U.S. Representative Gabrielle Giffords in Arizona.
Cali Wilson, 7, draws a rainbow on a poster at the office of U.S. Rep. Gabrielle Giffords in Tucson, Arizona, Jan. 16, 2011.
November 2009: U.S. Army psychiatrist kills 13 people at Fort Hood, Texas.
April 2007: Virginia Tech student kills 32 people before committing suicide.
October 2006: Gunman kills five girls in Pennsylvania Amish school before committing suicide.
January 2006: Ex-postal worker kills eight before committing suicide in California in rare case of female shooter.
April 1999: Two Columbine High School students kill 12 students, one teacher and themselves in Colorado.
November 1991: Gunman kills four University of Iowa faculty members and a student before committing suicide.
October 1991: Gunman crashes pickup into a Texas cafe, then begins shooting; kills 23 people before committing suicide.
August 1986: Gunman kills 14 postal workers in Oklahoma before committing suicide.
July 1984: Gunman kills 21 people at a McDonald’s in California before being killed by police.