On June 12, 2016, a mass shooting occurred inside Pulse, a gay nightclub in Orlanda, Florida, in which 49 people were killed and 53 injured by a lone terrorist identified as Omar Mateen. The terrorist was killed by the Orlando police after a three-hour standoff. It was the deadliest mass shooting by a single gunman in the United States and the deadliest incident of violence against LGBT (lesbian, gay, bisexual and transgender) community in the US. Most of those harmed were of Hispanic background. It was widely denounced both as an act of terrorism and a hate crime.

The assailant was identified as 29-year-old Omar Mateen, an American born to parents of Afghan background. Witnesses said he was a regular patron of the nightclub and had used gay dating websites in the past. He gave a call to 911 during the attack and swore allegiance to the Islamic State of Iraq and the Levant (ISIL). The Central Intelligence Agency (CIA) said it found no links between ISIL and Mateen. He has been reported to have expressed hostility towards LGBT people and other minorities.

The Federal Bureau of Investigation (FBI) has come under criticism for handling of the Omar Mateen case. It is said that he was interrogated twice by the FBI and that the gun shop owner had alerted the FBI about the purchase of a military-type assault weapon. There is major debate going on in the US on gun control laws and how it is easy to get military-type weapons by individuals.