He would go to the ends of the Earth to find a suspect.
The bloodshed was the latest in what seems to be a never-ending string of mass shootings that are happening with terrifying frequency across the United States.
Witnesses described a man cloaked in black and wearing glasses as he walked onto a dance floor filled with people.
Sources told NBC News he is a white male who is "heavily tattooed".
With files from The Associated Press.
Numerous law enforcement agencies were on-scene, including the FBI and the federal Bureau of Alcohol, Tobacco, Firearms and Explosives. Dean says Helus was his longtime friend and gym partner and planned to retire soon after 29 years with the force.
Twelve people are dead and at least eleven more were injured after a mass shooting inside a popular California bar on Wednesday night.
How did the shooting occur?
People watch police responding to the shooting on November 7, 2018.
How to Find the 2018 iPad Pro in Stock
The publication also points out that the iPad Pro's own processor and graphics performance should not be underestimated. However, you won't be able to contort the keyboard in a way to use it without the keys in front of you.
Newlyweds killed in tragic helicopter crash after their wedding
The helicopter had taken off a few kilometres away from the family ranch in Uvalde, Texas , where the ceremony was held. Bailee Ackerman and William Byler were married Saturday, before being whisked off to a ranch near Uvalde, Tex.
Lowe's to close 31 stores across Canada
The hardware store has five locations in Sacramento County: in Sacramento, Elk Grove, Rancho Cordova, Citrus Heights and Folsom. Lowe's says it expects to close the impacted stores by the end of the company's 2018 financial year, February 1, 2019.
"I've learned it doesn't matter what community you're in", Ventura County Sheriff Geoff Dean told reporters when asked if he was surprised this happened in Thousand Oaks.
"We're very proud of who he is", one person said.
Pepperdine University said some of its students were at the bar, and it's working to identify them.
The Borderline Bar & Grill website promoted Wednesday's country music event. Once safely outside, the uninjured hugged and awaited word about those still inside. "One bar stool and straight through a window", he told reporters.
The married father-of-one was among 12 people to have been killed by the 28-year-old US Marines veteran, who is believed to have later turned the gun on himself.
The shooter was armed with a Glock 21.45-caliber handgun with an extended magazine that he purchased legally, police said. "Multiple injuries reported", the Ventura County Fire Department tweeted.
Long was "the victim of a battery" at a bar in Thousand Oaks in January 2015, Dean said.
Map of California locating shooting at a bar in Thousand Oaks.
"Great bravery shown by police". But as the two made their way inside, Helus was shot several times.
Sergeant Helus and another officer from the Highway Patrol arrived at the scene of the massacre at 11.23pm last night - three minutes after the 911 call went out.