LAS VEGAS -- As gunfire rang out at a music festival on the Las Vegas Strip overnight, people documented the terror on social media.

We've seen video in tweets, which you can hear multiple rapid-fire gunshots ringing out as Jason Aldean was on the stage at the Route 911 Harvest Festival near the Mandalay Bay Hotel and Casino.

Confusion quickly turned to fear and on some of the tweets, you can see people running for cover.

More: WATCH LIVE | Las Vegas strip shooting, continuous coverage from CBSN

At least 20 people were killed and more than 100 injured in the shooting. They say the gunman was killed.

Below are some of the tweets we've seen from the chaos. If you're viewing on our mobile app, you can see them by tapping here.