Facebook has activated its 'safety check' feature following the deadly mass shooting at a music festival in Las Vegas.

Those in the Vegas area may be prompted to click an "I'm safe" button that will left friends and family know they are okay. You can visit Facebook Safety Check to be shown which of your friends were in the area and who has marked themselves 'safe.'

Authorities have also set up a hotline for family or friends to report a missing loved one connected to the incident. That number is 866-535-5654.

Las Vegas Police have also opened up a family reunification center at its headquarters at 400 S. Martin L. King Blvd. in Building B. The FBI in Vegas is also asking anyone with pictures or videos to send them in.

PHOTOS | Fatal shooting on Las Vegas strip