At least 58 people were killed and more than 500 wounded when a gunman opened fire on an outdoor music festival on the Las Vegas Strip in the worst mass shooting in modern US history.
Previously, the deadliest mass shooting had been an attack at an Orlando, Florida, nightclub that killed 49.
Before that, the deadliest shooting in the US was the 2007 attack at Virginia Tech, in which a student killed 32 people before killing himself.
Here's a look at some of the nation's deadliest rampages:
• Las Vegas, October 1, 2017: A lone wolf gunman kills at least 58 people, injures 515 after shooting people from a high-rise Las Vegas hotel
• Orlando, June 12, 2016: A gunman fatally shoots 49 people at gay nightclub Pulse before he is shot dead by police
• 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 man shoots dead his mother, then kills 20 children, six adults and himself at Sandy Hook Elementary School in Newtown, Connecticut
• San Bernardino, December 2, 2015: A husband and wife kill 14 people at a workplace holiday party in San Bernardino in Southern California before dying in a shootout with police
• Columbine, April 20, 1999: Two teenagers rampage through Columbine High School in Littleton, Colorado, shooting dead 12 students and a teacher and wounding more than 20 others before killing themselves
• Binghamton, 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: An army major and psychiatrist opens fire at Fort Hood, a US Army base in Texas, killing 13 people. He is sentenced to death
• Washington DC, September 16, 2013: A former Navy reservist working as a government contractor kills 12 people at the Washington Navy Yard. He is shot dead by police
• Colorado, July 20, 2012: A masked gunman kills 12 people and wounds 70 when he opens fire at a midnight premiere of Batman film The Dark Knight Rises in Aurora, Denver. He receives a life sentence
• Washington DC, October 2002: Two men ambush 13 people, killing 10 of them, in sniper-style shootings that terrorise the Washington area for three weeks. One sniper was executed and the other was sentenced to life in prison
• Oregon, October 1, 2015: A man opens fire on the Umpqua Community College campus in southwest Oregon, killing nine people before he is shot dead by police
• Charleston, June 17, 2015: A white supremacist kills nine black churchgoers at a historic, predominantly black church in Charleston, South Carolina
• Waco, May 17, 2015: Rival motorcycle gangs kill nine at a restaurant in Waco, Texas. More than 170 people are arrested
• Wisconsin, August 5, 2012: A white supremacist kills six worshippers in a Sikh temple in Oak Creek, Wisconsin. The gunman kills himself
• Tucson, January 8, 2011: Then-US representative Gabrielle Giffords is the target of an assassination attempt by a gunman in Tucson, Arizona. Six people are killed and 13, including Giffords, are wounded
• Amish school, October 2, 2006: A gunman kills five girls in a one-room Amish schoolhouse in Nickel Mines, Pennsylvania, before killing himself.