A country music guitarist has changed his position on gun control after surviving a deadly mass shooting at a Las Vegas music festival that left him fearing for his life.

Caleb Keeter, lead guitarist of the Texas-based Josh Abbott Band, took to Twitter on Monday to share his personal experience in the wake of the shooting that left at least 58 people dead and hundreds injured. Keeter said he had supported the Second Amendment all of his life – until Sunday.

"I cannot express how wrong I was," Keeter wrote. "We actually have members of our crew with [Concealed Handgun Licenses] licenses, and legal firearms on the bus. They were useless."

The Josh Abbott Band performed as part of the Route 91 Harvest Festival, a three-day country music festival that ended Sunday in Las Vegas. Authorities said 64-year-old Stephen Paddock of Mesquite, Nevada, opened fire into a crowd there. Paddock fired from the 32nd floor of the Mandalay Bay Hotel and Casino across the street from the concert, and police said Paddock killed himself after the shooting.

As the death and injury tolls rise, the shooting is being regarded as the deadliest in modern U.S. history.

Frontman Abbott reported that some of the band's members and crew members were on the concert grounds during the shooting and witnessed injuries. Some of the crew members were hit with shrapnel but not injured, according to a post on the band's official Facebook page.

Abbott joined celebrities and politicians in sending his condolences to the victims and their families on behalf of the band, and he shared some of his personal experience on Twitter.

"I'll never unhear those gunshots; and our band & crew will never forget how that moment made them feel. Our hearts are with all the victims," Abbott wrote.

I'll never unhear those gunshots; and our band & crew will never forget how that moment made them feel. Our hearts are with all the victims — Josh Abbott (@joshabbottband) October 2, 2017

But Keeter took his reflection a step further, sharing a story of how he drafted goodbye messages to his family and thought he would not survive. The night proved pivotal in shaping his political beliefs.