The police officer who died during the Wednesday night (Nov. 7) mass shooting at the Borderline Bar & Grill in Thousand Oaks, Calif., is being hailed as a hero, by both law enforcement officials and country artists. On social media, Charlie Daniels and others are paying their respects to Sgt. Ron Helus.

"Another Blue Knight was lost last night. He died in the act of protecting and serving, as so many of his brothers and sisters have before him," Daniels writes on Twitter. "Sgt. Ron Helus, you died saving lives. There is no higher calling. Rest In Peace. Sincere condolences to the family and coworkers."

Helus, one of the first two first responders on the scene, was shot and killed after entering the venue, in which a gunman had opened fire. After he and a California Highway Patrol colleague arrive on the scene and entered the Borderline Bar & Grill, Helus "was struck multiple times with gunfire," according to Ventura County Sheriff Geoff Dean. Helus' partner brought him to safety, but the 29-year police veteran later died at the hospital.

"He was hard-working, he was totally committed, he gave his all and, tonight, as I told his wife, he died a hero," says Dean (quote via CNN). "He gave his life to save other people."

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Helus leaves behind a wife and son; the Los Angeles Times reports that he called his wife before entering the bar. Helus was looking forward to retiring soon, Dean says.

“It’s so tragic losing Ron,” Dean adds. “We go to the gym together, work out together. It’s horrific and terrible and it saddens our hearts.”

Twelve people are dead following the Wednesday night shooting. The Borderline Bar & Grill was hosting "college country night" when a tall, white male, dressed in all black, entered and began shooting around 11:20PM local time. The shooter, 28-year-old Ian David Long, was killed by a self-inflicted gunshot wound.

Some of those in attendance were also at the Route 91 Harvest Festival shooting in October 2017. Nicholas Champion tells CBS that he and "probably 50 or 60 others who were in the building at the same time as me tonight" were also at the 2017 Route 91 Harvest Festival in Las Vegas, Nev., at which 58 people died when a gunman opened fire on the crowd from the nearby Mandalay Bay hotel.

Photos From Outside the Thousand Oaks Shooting

According to its website, the Borderline Bar & Grill is "Ventura County's Largest Country Dance Hall & Live Music Venue." Borderline has been open since the late 1980s, when it was located in Malibu, Calif.; it moved to Thousand Oaks in 1993. Artists such as Lee BriceTyler Farr and more have performed at Borderline over the years.

Thousand Oaks is located about 40 miles west of Los Angeles, and was recently ranked as the third-safest city in the United States by Niche.com, which analyzes "crime rates for murder, assault, rape, burglary and other crime statistics by city ... based on data from the FBI and U.S. Census."

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