LAS VEGAS (AP) — The head of New Jersey’s state police union was heading back to his room at a Las Vegas hotel when a gunman staying three floors above him opened fire on a crowd of concertgoers there, killing at least 58 people.

Police: Shooting On Las Vegas Strip Kills At Least 58, Wounds More Than 500

Patrick Colligan was at the Mandalay Bay Resort and Casino for a seminar. He had just finished dinner Sunday night when he saw a security guard and a police officer run by. More armed officers soon arrived on scene.

Colligan says he had no idea what was happening. But he saw people running and ducking during what he describes as “kind of like controlled chaos.”

Witness: ‘Everybody Thought They Were Gonna Die For 20 Minutes’

Colligan, who is president of the New Jersey State Policemen’s Benevolent Association, was staying in a room three floors below where the shooter was.

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