Some New Jersey residents have returned home safely after witnessing Sunday's mass shooting at a country music festival in Las Vegas.

Authorities say gunman Stephen Craig Paddock opened fire from a 32nd-floor room of the Mandalay Bay hotel-casino, killings dozens of people and wounding hundreds more. The 64-year-old Nevada man killed himself before authorities made their way inside his room.

Vincent Ramirez, of Edgewater, was locked inside the Mandalay Bay for hours as the shooting unfolded.

"That commotion broke loose...that's when you're really freaking out...because we don't know what's going to happen," Ramirez says.

Patrick Colligan, of the New Jersey Police Benevolent Association, was having dinner at the Mandalay Bay when the gunfire erupted. He didn't hear those shots, he says, but recognized the signs of an active shooter.

"Elevators were shut down and at that point police officers were yelling, '32nd floor, we have to get to the 32nd floor," he recalls.

Colligan was unarmed at the time but says he trains for events like active shooter situations, adding there was nothing more that could have been done.

"You could have scanned everybody going into that -- all 22,000 people could have been wanded and strip-searched and there was still going to be...deaths," he says.

The massacre marked the deadliest mass shooting in modern Untied States history.