According to authorities, a gunman marched into Pulse nightclub at 2 a.m. on Sunday morning and opened fire.

What you should know

• A gunman, Omar Mateen, 29, of Port St. Lucie, Florida, killed 50 people at Pulse Orlando, a gay nightclub in Orlando, Florida, on Sunday morning at around 2 a.m.
• A police officer was stationed near the nightclub and engaged in a gun battle with Mateen.
• After the interaction, Mateen took hostages inside the club.
• Police raided the club at around 5 a.m. and used a controlled explosion to distract Mateen.
• They entered the club, killed him and saved at least 30 hostages.
• Approximately 53 people were taken to the hospital.
• A homeland security advisor briefed President Obama, and the White House is treating this as a terrorist attack.
• Police believe at least 50 people lost their lives, and 50 others were injured during the attack.
• The FBI suspected Mateen of being an ISIS sympathizer.
• Most of the killing was done with an assault rifle.

The gunmen, who has been identified as Omar Mateen, took several people hostage but was eventually killed by the police. During a press conference, Orlando Police Chief John Mina said “Our SWAT officers exchanged gunfire with the suspect. The suspect is dead.” Mina added, “He appeared to be carrying a rifle, an assault-type rifle, and a handgun and had some type of device on him.”

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Authorities originally identified the suspect as “not from this area” and “was organized and well-prepared.” FBI Agent Ron Hopper believed Mateen may have followed Islamic extremist ideologies.

Pulse reacted to the event quickly on social media and said, “Everyone get out of pulse and keep running.”

Special Agent Danny Banks of the Florida Department of Law Enforcement said “We are investigating this from all points of perspective as an act of terrorism.  Anytime we have potentially dozens of victims in any of our communities then I think we can qualify that as terrorism activity. Whether that is domestic terrorism activity or an international one is certainly something that we will get to the bottom of.”

H/T: Orlando Sentinel