At least 12 people have died, and as many as 15 more are injured after a mass shooting that took place at a country bar called Borderline Bar & Grill in Thousand Oaks, Calif., late Wednesday night (Nov. 7).

ABC News reports that a white male gunman burst into the bar where hundreds of people were gathered, throwing a smoke device to cause confusion and firing dozens of rounds into the crowd. Authorities responded to Borderline just before midnight, including California Highway Patrol, a SWAT team and FBI.

Ventura County Sgt. Ron Helus was one of the first officers on the scene, and he was struck multiple times as he entered the bar through the front door. Helus — a 29-year veteran of law enforcement who intended to retire in a year — was among the at least 12 fatalities of the shooting, and one other person suffered a gunshot wound, while as many as 15 others sustained various injuries trying to escape the scene. So far the reported fatalities include 11 victims and Helus.

Other confirmed victims include Alaina Housley, the niece of former Fox News reporter Adam Housley and Sister, Sister actress Tamera Mowry-Housley; 22-year-old Cody Coffman; 23-year-old Justin Meek; Sean Adler; 21-year-old Blake Dingman; Marine Corps veteran Daniel Manrique; dancer and artist Noel Sparks; 27-year-old Navy veteran Telemachus Orfanos; 21-year-old Jake Dunham; Mark Meza; and Kristina Morisette.

The gunman has been identified as 28-year-old Ian David Long, a Marine veteran with PTSD. He was found dead at the scene, and authorities believe he took his own life.

Speaking to Good Morning America, Teylor Whittler, who was at Borderline celebrating a friend's birthday, described the scene as the shooting took place.

"A bunch of people dog-piled on top of each other," she says." "Everyone just yelled, 'Run, he's coming!'" She says she stumbled and fell, and multiple other people stumbled over her before a man helped her to her feet. Whittler says multiple other men gathered around a group of people who were trying to escape, "ready to take a bullet for every single one of us."

21-year-old Taylor von Molt is a promoter at Borderline, and she tells CNN that when the shooting began, people were line dancing, and she thought the initial gunshot she heard was a balloon popping.

"I was confused because we didn’t have any balloons at the time... I turned around and saw him fire his weapon a couple of times and I ran to the nearest exit and tripped and fell on the way.," she recalls.

Ventura County Sheriff Geoff Dean described the scene inside the bar after the mass shooting in Thousand Oaks as "horrific," with "blood everywhere." The motive for the shooting was unclear as of Thursday morning (Nov. 8). According to Dean, Long used a Glock 21 in his shooting rampage. The .45-caliber handgun is designed to hold 10 rounds plus one in the chamber, according to the AP, but Dean says Long's weapon featured an extended magazine that is illegal in the state of California, and he did not know how many rounds that magazine can hold.

Dean hailed Sgt. Helus — who had a wife and son — for his bravery, choking back tears as he recounted how the fallen officer ran toward the Borderline within three minutes of the first reports of gunfire.

"He gave his all, and tonight, as I told his wife, he died a hero," Dean said (quote via NBC News). "He went in to save lives, to save people."

President Trump turned to Twitter to react to the shooting on Thursday, lauding the "great bravery shown by police." He has ordered the U.S. flag to be flown at half-staff in respect for the victims until sunset Saturday at the White House and on all public buildings, military posts, naval stations and aboard all U.S. naval vessels.

Borderline Bar & Grill's website describes the venue as "Ventura County's Largest Country Dance Hall & Live Music Venue," listing John Rich, Collin Raye, Mark Chesnutt, Lee Brice and Tyler Farr among the artists who have performed there over the years.  Rich was among the country artists who responded to the tragedy on Twitter Thursday morning, along with Charlie Daniels, Morgan Wallen. LeAnn RimesMargo Price and more.

This is a developing story. Taste of Country will update developments in the mass shooting in Thousand Oaks, Calif., as they happen. 

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