“An armed man dressed in black opened fire late Wednesday night inside a crowded country and western dance hall in Thousand Oaks, Calif., killing at least 12 people, including a sheriff’s deputy who had responded to the scene. The gunman was also dead.”

“The shooting came just over a year after 58 people were killed at a country music festival in Las Vegas when a gunman opened fire from a high-rise hotel room. There was an eerie parallel between the two shootings as some of the same people who emerged from the bar, the Borderline Bar & Grill, described having survived the shooting on the Las Vegas Strip.”

“Witnesses recalled a chaotic scene at the bar, which was filled with hundreds of people, many of them college students: A gunman opening fire, first at a security guard, as patrons dropped to the dance floor, hid under tables and broke windows to escape.”

“The Ventura County sheriff, Geoff Dean, said there were “multiple other victims of different levels of injuries.” His voice cracking, he identified one victim as Sgt. Ron Helus, who was shot when he entered the building.”

“He died a hero because he went, he went in to save lives, to save other people’s lives,” Sheriff Dean said.

“When other law enforcement officers arrived, he added, the gunman was already dead. “

Country music was playing in the dimly lit bar when people first heard gunshots some time before midnight. Some said they had initially mistaken the sounds for firecrackers.

“Ms. Worrell ducked for cover and heard a barrage of bullets. As she ran out of the bar, she said, she saw several bodies sprawled on the floor. Hours after the shooting, she had still not heard from 2 friends who had been with her at the bar.”

“One young woman inside the bar, Teylor Whittler, said the gunman appeared focused and did not appear to be targeting anyone in particular.”

“I saw him shoot,” Ms. Whittler said, adding that someone had yelled, “Everybody get down.”

She said she saw him quickly reload his gun and fire again. “He knew what he was doing,” she said. “He had perfect form.”

“People started running to the back door,” she said, and she heard someone shout, “Get out — he’s coming.” She then fled and heard another burst of gunfire.

“Brendan Kelly, 22, helped several people escape from inside. “It’s your worst nightmare,” he said. “It’s terrible.”

“The attack in Las Vegas — and the mass shooting at a high school in Parkland, Fla., in February — renewed the debate about the prevalence of guns in the United States and their connection to the high number of mass shootings in the country.”

“The rampage in Thousand Oaks, a city of 129,000 people about 40 miles west of Los Angeles, was the deadliest shooting in Southern California since 14 people were killed in a terrorist attack in San Bernardino, Calif., in 2015.The first 911 call reported “shots fired” at the club, said Capt. Garo Kuredjian, a spokesman for the Ventura County Sheriff’s Office. “As deputies responded, they also heard shots.” Additional units from the California Highway Patrol, Simi Valley and the F.B.I. responded.”

“Captain Kuredjian said many of the young people inside the crowded bar had turned out for a college country music night. The bar is not far from Pepperdine University, which said in a statement that it had received reports that several students were at the bar when the shooting occurred.”

“The bar’s website says that for a quarter century, it “has stood as the Ventura County’s largest country dance hall and live music venue,” with more than 2,500 square feet of open dance space.”

“Ms. Wong, who was celebrating her birthday, was trapped in the club until the police arrived. She described the scene as a blur.”

“She’s alive though. She’s alive for her 21st birthday,” said Ms. Whittler, whose badly scratched leg had just been bandaged by emergency medical workers. Moments later, Ms. Whittler’s parents arrived in a truck to check in on her.”

“Were you hit?” her mother asked, with panic in her eyes. “No it’s just a scratch, I’m fine, I’m fine,” Ms. Whittler said.

Jason Coffman was frantically searching for his son, Cody, 22, who had planned to go to Borderline on Wednesday night. Calls to Cody’s cellphone went unanswered.

“I am in the dark right now,” Mr. Coffman said on CNN. “It’s actually tearing me up.”

“I started hearing these big pops,” said the witness, a man who was not identified. “The gunman was throwing smoke grenades.”

“Then, panic ensued as people tried to flee.”

“He just kept firing,” the witness said.”

“Michael Millar, 25, who lives near the Borderline and is a regular, was on his way to the bar Wednesday night when people began to call him frantically asking if he was inside.”

“He said that the bar was popular with police officers and firefighters, and that it was often busy on Wednesdays because it hosts a college night and allows students under 21 to enter.”

As Mr. Millar and his friend Chris Weber walked toward the bar, which was surrounded by police tape, they received a call that a friend who worked the door had been shot. “She’s the sweetest, nicest girl,” Mr. Millar said”

“Nobody would expect this in Thousand Oaks.”

“Mr. Weber said that many of the people he believed were at Borderline had attended the music festival in Las Vegas last year where dozens died. He was frantically calling friends early 11/8/18 to try to confirm who was inside.”

“Young women who were at the Borderline expressed disbelief that the bar, which they sometimes go to several times a week, could become the site of such violence.”

Here are names of the victims:

Cody Coffman, 22 Sean Adler, 48 Sgt. Ron Helus, 54 Alaina Housley, 18 Dan Manrique, 33 Justin Meek, 23 Kristina Morisette, 20 Telemachus Orfanos, 27 Noel Sparks, 21 Jacob Dunham, 21 Blake Dingman, 21 Mark Meza Jr., 20

Depending on how mass shootings are defined and counted, the number of US mass shootings by November 2018 range from 307 to 376.

Variation in How Mass Shootings Are Defined and Counted