A 64-year-old retired accountant shot down 58 people from his hotel room at a crowd attending an outdoor country music concert on October 1, 2017.
Around 550 others were wounded in the attack. The accountant later committed suicide.
It is the worst mass shooting in modern US history.
Florida club: 49 killed
A heavily armed gunman opened fire inside a gay nightclub in the city of Orlando on June 12, 2016, killing 49 people. The attacker was killed in a shootout with police. He pledged allegiance to the Islamic State group, which later claimed responsibility.
Florida high school: 17 dead
A 19-year-old former student at Marjory Stoneman Douglas High School who was expelled for disciplinary reasons returned to the school in Parkland, Florida, and opened fire on February 14, 2018, killing 14 students and three adult staff members.
Sandy Hook: 26 killed
A 20-year-old man killed his mother in Newtown, Connecticut, on December 2012 before blasting his way into Sandy Hook Elementary School and shooting dead 20 six- and seven-year-old children and six adults. He committed suicide later.
Texas church: 25 killed
A 26-year-old man who was court-martialed while in the Air Force shot dead 25 worshippers during Sunday services and wounded at least 20 others at a Baptist church in the small rural community of Sutherland Springs outside San Antonio, Texas, on November 5, 2017. The shooter fled the spot and was later found dead in his car with a self-inflicted gunshot wound.
California office party: 14 dead
A radicalised Muslim couple stormed a Christmas office party at a social services center in San Bernardino on December 2015 and shot 14 people, wounding 22 others. They were later shot dead by police.
The picture shows personal belongings in the Redlands, California, apartment of the radical Muslim couple Syed Farook and his wife Tashfeen Malik.