Country star Jason Aldean says the Las Vegas shooting is “beyond horrific”.
He was performing at the Route 91 Harvest festival when a gunman opened fire, killing at least 50 people.
Videos posted online show the musician and his band stop playing as shots are heard and people begin screaming.
It happened at the end of the three-day festival, which featured some of the biggest names in country music, including Eric Church, Sam Hunt and Marin Morris.
Following the shooting, Jason Aldean posted an emotional message on Instagram.
The star, who’s sold 15 million albums and had 17 number one songs, said: “Tonight has been beyond horrific. I still don’t know what to say but wanted to let everyone know that me and my crew are safe.”
He goes on to say that it “hurts my heart” that people have been injured when they’d just gone to enjoy themselves.
The Route 91 Harvest festival was launched in 2014.
In previous years it’s had around 30,000 people watching each day. This year organisers promised a #ThreeDayNeonSleepover.
Jake Owen was on stage just before Jason Aldean. He posted messages while the shooting was going on.
Hours later he tweeted to say he was OK.
Although they may not be huge names in the UK, country stars have massive followings in America – with both young and old audiences.
Chris Young won the Nashville Star TV show in 2006. He wasn’t performing but was at the festival.
Lauren Alaina had performed on the main stage.
Kane Brown summed up his feelings with four simple words.