A gunman is believed to have opened fire from the upper floors of the Mandalay Bay Hotel and Casino.
The deadly shooting at a Las Vegas music festival late Sunday has resonated around the world.
Aldean wrote on Instagram "Tonight has been beyond horrific".
"My thoughts and prayers go out to everyone involved tonight".
Senator Ted Cruz, running against Trump for the Republican presidential nomination, summed up the political associations of the genre when he said he switched from listening to rock because he found country stars more patriotic after the September 11, 2001 attacks. Soon, the music comes to an abrupt halt and Aldean is seen fleeing the stage.
Shares of USA casino operators fell in early trading on Wall Street, with MGM Resorts International, which owns the Mandalay Bay, down 4 percent.
"They were on it quick", Kenny noted, insisting the ordeal hasn't broken his spirit: "Fear will not overcome us", he says. During Aldean's set, a gunman opened fire, killing at least 50 and injuring over 400, and Owen was there watching his friend perform.
Independence Day Speech: 'Buhari A Plaque On Nigeria'
The colorful ceremony had just ended as at the time of filing this report and President Buhari was about leaving Maiduguri. We should continue to pray for the unity of Nigeria". "This is indeed the Clarion Call for Nigerians to obey".
However social media was also filled with well wishes for Aldean and the victims of the tragedy, asking others to think what they'd do in the same situation. She says the first thing she wants to do when she gets home is to give her dog a great big hug.
"I turned around and I looked and people just started running", she said. "Active shooter at @Route91Harvest in Vegas".
"We're going to get trampled if we don't go", a bystander could be heard saying in a dramatic video of the incident.
Stanley said the gunfire started as they got in the hotel elevator back at the hotel.
The Las Vegas Police Department said people should avoid the area.
Gun shots! Vegas. Pray to god.
Officials at the University Medical Center in Las Vegas told ABC News that it had at least 20 victims with gunshot wounds right now, with the number expected to grow.