A country musician performing at the Las Vegas concert where dozens of people were killed said the attack has completely changed his view on gun control.
At least 59 people were killed and hundreds others injured at the Route 91 Harvest Festival in what's become the deadliest mass shooting in modern US history.
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Guitarist Caleb Keeter was performing as part of the Josh Abbott band at the event and said he's always been a staunch defender of the second amendment - the right to bear arms - until now.
"I cannot express how wrong I was," he said.
Keeter said several members of his crew had legal firearms on their buses, but "they were useless".
"We couldn't touch them for fear police might think that we were part of the massacre and shoot us," he said.
In the chaos and confusion, early witness reports suggested there were multiple gunmen who split off in multiple directions. Police later confirmed the attacker had acted alone.
Keeter said the shooter had "access to an insane amount of firepower" and said "enough is enough".
"Writing my parents and the love of my life a goodbye last night and a living will because I felt like I wasn't going to live through the night was enough for me to realise this is completely and totally out of hand," he said, adding that one of his crew members was injured by shrapnel.
"We need gun control RIGHT. NOW. My biggest regret is that I stubbornly didn't realise it until my brothers on the road and myself were threatened by it."
Warning: The tweet below contains explicit language which may offend some people.
Calls for gun control are routinely made after mass shootings, including last year's Pulse nightclub massacre - which was until Sunday (local time) the most deadly mass shooting in the modern history of the US.
Former US Secretary of State Hillary Clinton was criticised earlier on Monday for asking for politics to be put aside and for people to "stand up to the NRA [National Rifle Association]".
However, Keeter's message, shared on Twitter, was mainly welcomed by his fans.
"[Thanks] for crucial acknowledgement that more guns at a mass shooting scene makes things massively less safe for first responders, sow chaos," one person tweeted.
"You're going to take a lot of heat for this, but thanks for saying what you think and for coming around to a new point of view," another shared.