How To Use Facebook Safety Check In Orlando To Mark Yourself Safe For Your Friends & Family

Update: In a press conference Monday morning, Orlando police confirmed that 49 people had been killed and 53 injured early Sunday morning at Orlando's Pulse gay nightclub in the deadliest mass shooting in recent U.S. history. After opening fire on the crowd, an individual named Omar Mateen had taken hostages and was ultimately killed in a stand-off with police; Mateen had called 911 and pledged allegiance to the Islamic State shortly before the massacre. Orlando mayor Buddy Dyer declared a state of emergency, and the massacre is being investigated as an act of terrorism.

The victims' names were released by the city of Orlando on its website as their next of kin were informed. Here are some ways to help the Orlando shooting victims and their loved ones; you can also donate to the victims' fund, as well as express your solidarity with the LGBTQ community by posting a tribute online. You can also attend a vigil near you to honor the victims.

Earlier: At least 50 people have been killed by a shooting at a popular gay nightclub in Orlando, which occurred early Sunday morning. It's been labeled the worst mass shooting in U.S history, and loved ones of those in the Florida city scrambled overnight and into the day on Sunday to make contact with their connections in the area. While the panic and chaos continues, those in Orlando can use Facebook's Safety Check feature to mark themselves safe.

Upwards of 300 people were at Pulse, the nightclub where the shooting occurred, when the violence broke out around 2 a.m. The nightclub quickly alerted the public to the situation by posting on its Facebook page. "Everyone get out of pulse and keep running," Pulse posted around 2 a.m. According to other social media reports from eyewitnesses, including those in the nightclub, people began to escape through back doors. Others hid in bathrooms and outside under cars to shield themselves from the gunfire, which occurred both outside and inside the building.

Those who escaped, or were nowhere near Pulse on Sunday night, took to social media on Sunday to let their loved ones know that they were safe. In addition to posting and tweeting, though, those who are fortunately safe and still in the Orlando area can use a Facebook tool that's designated for emergency situations. It's called Facebook Safety Check and it's a quick way to get your most important message out to all of your connections at once.

Here's how Safety Check works: When an emergency — like a mass shooting — occurs, Facebook sends a notification to its users who are located in the relevant area. This notification can come as a regular notification when you sign in to Facebook, or as a text message notification. The notification asks users if they're safe from the danger, and then gives them the option to choose, "I'm safe," or, "I'm not in the area." Facebook also reports which of a user's friends have also marked that they're safe.

Facebook launched Safety Check more than a year and a half ago in October 2014. At that time, Facebook creator Mark Zuckerberg said, in a post on Facebook, that the team was inspired to create Safety Check after the tragic earthquake and tsunami that struck Japan a few years prior. When the tool launched, it was only used for natural disasters, but its use has expanded over time to include all kinds of emergencies.

If you don't live in Orlando, you probably won't see the Safety Check notification, but you may see an alert if one of your friends has marked that they're safe. Loved ones can also call the city of Orlando's crisis hotline to request information about an individual. The hotline phone number is 407-246-4357.