The president of New Jersey's largest police union was at the Mandalay Bay Hotel while the shooting in Las Vegas was happening.
Pat Colligan, the president of the New Jersey State Policemen's Benevolent Association, was in Las Vegas for a law enforcement seminar
He was on his way to his room when police ran through the Mandalay Bay casino.
"There was a lot of alarm as the police officers were running through. Then when I saw a SWAT team and I saw the look on their faces and the fact that they were moving through. Then people started to, I wouldn't call it panic, more controlled chaos, everybody was trying to get out. They were shutting down all the tables and just pointing for the employees to flee."
Colligan says he's used to being part of the response team during emergency situations, and it was odd to be a bystander who didn't know exactly what was happening.
He says it would be difficult to prevent that kind of shooting.
"Within view of that concert venue there's probably 2000 hotel rooms. A high-powered rifle, you have at least a mile distance that you can shoot somebody, it's impossible. And the real difficult is this guy breaks a window on the 32nd floor, you can't take a handgun from the ground and shoot back."
Colligan credits Las Vegas police for their rapid response in finding the gunman.