On 12 June 2016, security guard Omar Mateen perpetrated the deadliest mass shooting on American soil in recent at the Pulse nightclub in Orlando, Florida, killing (as of last reports)
49 people and injuring more than 50.

The incident occurred in the very early hours of 12 June 2016, and an initial harrowing Facebook warning from Pulse was published at 2:09 AM Eastern Standard Time:

everyone get out of pulse and keep running

Among initial information reported about Mateen was that he had on the radar of the Federal Bureau of Investigation (FBI) for a few years, although he not officially been placed on any watch lists:

In the midst of the attack, Mateen called 911 and pledged his allegiance to ISIS, according to two law enforcement officials. During Mateen’s 911 [call], he also made reference to the 2013 Boston Marathon bombers, Tamerlan and Dzhokhar Tsarnaev, officials said.

Mateen was “on the radar” of U.S. security officials for some time but was not the target of a specific investigation, law enforcement officials told ABC News.

FBI Special Agent in Charge Ronald Hopper said that the FBI had taken an interest in Mateen twice: first in 2013 after he made “inflammatory” comments to co-workers and then again the next year after he was linked to another U.S. radical who became a suicide bomber in Syria.

Mateen was interviewed by investigators three times in relation to the probes but, in both cases, the FBI determined Mateen was not a threat and closed the investigations, Hopper said.

He was not under investigation or surveillance at the time of the shooting, Hopper said.

Later on 12 June 2016, the FBI told news outlets that the investigation into Mateen, his motives, and the attack was in its very early stages, and during a press briefing the agency did not discount that Mateen might have had fundamental Islamic extremist motives but emphasized that every avenue of interest remained under investigation. They also clarified early erroneous reports about the scene:

At a press conference, an FBI spokesman said investigators believed the attacker may have had extremist beliefs, but cautioned that they were pursuing multiple leads.

An explosion was heard at the club at about 5am local time, which police said was a “distractionary device” used as part of the rescue mission to get to the hostages. The explosion caused some panic on the ground, which led to Orlando police tweeting to say it had been a “controlled explosion” and warning the media about reporting inaccuracies.

Police said the incident began at 2am when the gunman started firing and an officer on duty at the club exchanged shots with him. They said it then descended into a hostage situation. The situation was resolved three hours later when a SWAT team stormed the nightclub after receiving messages from club patrons who were hiding in the club while the gunman was still at large.

Local news sources in Florida published conflicting descriptors of Mateen after speaking to persons with whom he was acquainted. One former coworker claimed he had resigned from his job working alongside Mateen as a security guard because Matten was “unhinged and unstable,” further stating that higher-ups refused to discipline Mateen “because he was Muslim”:

Daniel Gilroy said he worked the 7 a.m. to 3 p.m. shift with G4S Security at the south gate at PGA Village for several months in 2014-15. Mateen took over from him for a 3 to 11 p.m. shift.

Gilroy, a former Fort Pierce police officer, said Mateen frequently made homophobic and racial comments. Gilroy said he complained to his employer several times but it did nothing because he was Muslim. Gilroy quit after he said Mateen began stalking him via multiple text messages — 20 or 30 a day. He also sent Gilroy 13 to 15 phone messages a day, he said.

“I quit because everything he said was toxic,” Gilroy said, “and the company wouldn’t do anything. This guy was unhinged and unstable. He talked of killing people.”

Gilroy’s statement conflicted with that of a female resident of the community where Mateen was stationed as a security guard, who provided an entirely different characterization of the shooter:

PGA Village resident Eleanora Dorsi, however, recognized Mateen’s face as a friendly one who guarded her gated community in western Port St. Lucie.

“Whenever I saw him, he was very polite,” Dorsi said Sunday from her summer home in Connecticut. “He was always a gentleman.”

Dorsi, who has lived in the community since 2011, estimated that she saw Mateen a dozen times through the years, but he left a big impression on her because of his chivalry, she said.

Orlando Police relied heavily on social media outlets such as Twitter and Periscope to keep the public informed about the situation, both as it unfolded and its aftermath. Along with the FBI, Orlando Police implored media outlets to confirm the veracity of information related to the shooting before reporting it:

 

Orlando Police first asked anyone with information about Mateen to come forward, later directing such tips to the FBI. A recurring theme in OPD tweets was a plea to the press to note that all official information originated only with them:

Twitter was later used by police for four important updates about the incident:

ATF: The gunman legally purchased the firearms within the last week. In Florida. — Orlando Police (@OrlandoPolice) June 12, 2016

 

Although law enforcement agents were proactive in rapidly disseminating information directly to the public via social media, interest in the Pulse nightclub shooting and its unprecedented scope was extremely high. A number of social media items were rapidly spread in the shooting’s aftermath, ranging from mostly true to entirely false.

An early, popular Facebook claim held that more than one individual was believed to be involved in the Orlando mass shooting. A Facebook post claimed a survivor of the Pulse nightclub shooting said that at least three shooters perpetrated the incident, and repeated an inevitably popular detail that police suppressed the information so as not to cause public alarm. Very similar rumors spread in New York City, Illinois, and ahead of Black Friday following the November 2015 Paris attacks. The same sort of claim also reared its head after the December 2015 San Bernardino mass shooting and was somewhat perennial in London. Rumors of that stripe reflect a number of reactions to tragic acts of violence, helping to dissipate fear by providing citizens with a sense of security from being “in the know.” However, law enforcement agencies across the United States have been exceedingly proactive with respect to informing the public of potential future terror threats.

The Pulse nightclub shooting’s details also involved the intersection of a number of hot-button issues in the United States. The incident occurred on a Latin night at a gay venue and was perpetrated by a Muslim man, factors which social media users tended to view through the lenses of their own political leanings. One rumor held that shooter Omar Mateen was a Democrat and a leftist. It was true Mateen registered as a Democrat in 2006, but little is known about his political leanings at the time of the shooting.

Another rumor related to feelings of helplessness and a desire to spread useful information in the days after the attack, one holding that airline JetBlue was offering free flights and travel assistance to the families of the massacre’s victims. Many online users were unsure the claim was legitimate due to a paucity of official information from the airline, but JetBlue confirmed to us that the rumor was true and may have been subtle in their dissemination of publicity in order to avoid the appearance of capitalizing on the tragedy.

Mateen’s purported self-identification with Islamic State operatives (or ISIS) rejuvenated interest in claims that an ISIS “kill list” revealed places in which potential future attacks would occur. But the list in question was old and of questionable provenance at the time of its original circulation, and Orlando was not among the four cities in Florida included on that list.

Another popular theme in rumors circulating after major tragedies involved the use of crisis actors in connection with staged “false flag” attacks, and the Orlando nightclub shooting predictably led to such claims on Facebook and Twitter:

orlando shooting crisis actors

Rumors about crisis actors are part of a larger tendency among conspiracy-minded social media users to distrust the “official narrative” of any newsworthy tragedy. After a gunman shot and killed two journalists in Virginia in 2015, social media posts claimed that timestamps revealed the incident was a hoax. That claim was later debunked as a function of Twitter’s time zone rendering.

Crisis actors became a popular conspiracy claim after the 2012 Sandy Hook shootings, and the rumors appeared again after the Boston Marathon bombings in 2013. The claims snowballed after several high-profile mass shootings, culminating in a rumor that the “same girl crying” was present at massacres in Sandy Hook (Connecticut), Aurora (Colorado), Boston, and Oregon. However, those women were easily identified as four different persons (Carlee Soto, Amanda Medek, a vigil attendee, and Jessica Alvarez respectively). An unfortunate and cruel side effect of the meme’s popularity is that the depicted women were unwittingly cast into the spotlight during subsequent tragedies and unfairly labeled as government operatives.

Late on 13 June 2016, Fox News reported the FBI was investigating whether Mateen possibly had additional plans to target nearby Disney World or Downtown Disney. However, neither of those leads were concrete. Mateen was also rumored to be a visitor of Pulse in the past (as well as a user on gay dating app Grindr), but that too had not been confirmed. 

Florida-based Chick-fil-A famously maintained a policy of keeping its doors closed on Sundays, but lifted that decades-long directive on 12 June 2016:

The Atlanta-based chain known for being closed on Sundays said they weren’t sure of how many, but did confirm that several Orlando area stores prepared meals following the attack at a popular nightclub, providing food and any additional assistance to those in need.

In a statement, Chick-fil-A said: “Orlando is in our hearts and prayers.”

One Chick-fil-A location posted a photo of their flags at half-staff and the following message to their Facebook page:

“God Bless the USA. Home is where the (heart) is. Orlando is our home. ‪#‎prayfororlando.”

It wasn’t clear whether Chick-fil-A locations were open for business on a limited basis, or simply operated to prepare food to donate to the Orlando shooting’s first responders.