Country music star Jason Aldean confirmed his safety on Instagram early Monday morning after gunshots went off while he was performing on stage at the Route 91 Harvest country music festival in Las Vegas.

Aldean was reportedly singing the last song of his set, "When She Says Baby."

A witness told Fox News that Aldean rushed off the stage as soon at the gunshots went off.

The gunshots were heard at about 10 p.m. local time near Mandalay Bay Hotel and Casino.

Concert-goers reported seeing muzzle flashes from the upper floors of the Mandalay Bay Hotel and Casino.

Aldean’s wife, Brittany Aldean, also took to Instagram to offer her thoughts and prayers for the victims.

Many fans of the singer took to Twitter to express their shock and support.

Witnesses said they saw multiple victims as they fled the gunfire raining down on the concert venue. Some later huddled in the basement of the nearby Tropicana hotel-casino.

Some officers took cover behind their vehicles while others carrying assault rifles ran into the Mandalay Bay Hotel and Casino.

Concertgoers said they initially thought the gunshots were firecrackers.

This is the fourth time the country music festival was being held in Las Vegas and this year it was headlined by popular singers like Eric Church, Sam Hunt, Maren Morris, the Brothers Osborne, Lee Brice, Kane Brown, and Lauren Alaina, The Las Vegas Weekly reported.

The Associated Press contributed to this report.