(CNN) Bryan Hopkins hid in a freezer with dozens of others while the deadliest mass shooting in US history unfolded in Las Vegas late Sunday night. On Monday morning, he described his experience on CNN's "Newsroom."

Hopkins, a musical artist who had been at the Route 91 Harvest Festival, said the gunfire, which was later revealed to be coming from the 32nd floor of the Mandalay Bay hotel, was "constant."

"Then it would stop for, I don't know, a few seconds, and then it would start again," he told anchors John Berman and Poppy Harlow.

Hopkins said he attempted to lead a group to a fence that he recalled seeing. "We see an ice chest -- it's a trailer -- and we open up the doors and just start helping people up inside this trailer, which happened to be a freezer," he said. "There must have been, I don't know, 23 to 30 of us inside this freezer."

Hopkins said that some in the freezer worked to calm down the others while he opened the door and discovered the gunfire was still raining down on the festival.

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