Suddenly, a man wearing a black trench coat and sunglasses approached the door and shot the security guard at the entrance.
Inside the bar, some people heard popping sounds and kept on dancing, thinking it was fireworks sound effects from the song, witnesses said.
Within seconds, the gunman burst into the bar and without a word, fired into the crowd with a Glock .45-caliber handgun. People dropped to the ground and hid under pool tables and bar stools. Some piled on top of one another as others slammed bar stools against windows to break them.
Those who got out ran, the sounds of rapid gunfire echoing around them in the dark.
“They ran out of back doors, they broke windows, they went through windows, they hid up in the attic, they hid in the bathroom,” Ventura County Sheriff Geoff Dean said.
With every gunshot, they shivered
Students from several nearby universities frequented the popular bar. When the gunfire erupted shortly after 11 p.m. local time Wednesday, it was packed with young people, including a group celebrating a birthday.
Sunny Leon was at the back of the dance floor, and initially thought it was fireworks initially, she said. Then she thought it was a part of the song. “It sounded really weird,” she said.
When the sounds grew louder and closer, people started screaming. She dropped to the ground and crawled closer to the bar.
“I remember when I was on the ground, seeing a girl getting trampled. Because I was against the wall, I was OK. But she was getting trampled,” she said.
Tristan Appleby said he watched everything unfold from across the room. He saw a man dressed in black holding a gun with a flashlight and repeatedly shooting people laying on the ground.
“Luckily, he didn’t come my way,” Appleby said. “I was across the room behind a pool table hiding underneath with my friends.”
Appleby said with the every shot, the people lying underneath him shivered and squirmed. He kept his eye on the gunman and when he paused to reload, he whispered to others that it was time to dash to the exit.
“I said we go, and we ran,” he said. “I don’t know how I survived because at any moment, I could have been shot.”
She followed her friend’s orders and lived
Sarah Rose Deson was at the club for her friend’s 21st birthday. When the gunman burst in, her friend, Cody Coffman, yelled for her to get down.
“I fell to the floor and hid behind him and just tucked myself in his back,” she said. There was “a bunch of sparks and smoke everywhere,” she said. Shortly afterward, Coffman told her it was time to get out.
“I don’t even remember in this blur, but I ran for my life,” Deson said. She got out through the front entrance — the same one the shooter stormed through moments before — tumbled down in the parking lot, got up and kept running. She stopped when she got to a nearby gas station.
She later found out that Coffman did not make it.
“He’s one of the reasons that I’m here right now,” she said. “I didn’t know what to do. I just followed him, I dropped down and I hid with him. I know he was put in my life for a reason. He’ll always be my hero, and now he’s my angel. I’m going to live my life for the both of us”
Deputies arrived within minutes
The shooter was identified as former Marine Ian David Long, 28.
A few minutes after the first gunshots were reported, Helus and at least one California Highway Patrol officer rushed into the bar. The gunman exchanged gunfire with Helus, fatally wounding him.
A patrol officer pulled Helus out of the bar and waited for reinforcements.
Police said it was probably close to 15 minutes after they didn’t hear any shots fired that they regrouped, got additional officers and went back in. Long had fatally shot himself inside an office next to the bar’s entrance, Dean said.
Police found patrons holed up in the attic and knocked on the door, telling them it was OK to come out. Some people were so terrified, they asked officers to confirm it’s not the gunman.
Within 15-20 minutes, the scene was secure. Outside, frantic parents gathered, looking for their children.
CNN’s David Allan and Jason Carroll contributed to this report.