The Borderline Bar & Grill lists a "College Country Night" which takes place on Wednesdays, and is said to be popular with students. Once safely outside, the uninjured hugged and awaited word about those still inside. Helus was shot multiple times upon entering the bar and later died at a hospital.
Mr Coffman told reporters that his son - who had two younger brothers, aged eight and six - had been planning to join the military and was also looking forward to the arrival of a baby sister later this month.
The identity of the gunman is allegedly 28-year-old David Ian Long, a military veteran who apparently drove his mother's vehicle to the scene.
Long also had been a victim of battery at a different Thousand Oaks bar in January 2015, the sheriff said. The marine corps told news organizations that Long served in Afghanistan between November 2010 and June 2011.
The killer was identified as Ian David Long, a 28-year-old veteran who authorities said had an episode of erratic behavior last spring that was thought to be post-traumatic stress disorder because of his military background. The sheriff believes Dean took his own life. Investigators are working out the details of what transpired, Dean added.
But Dean said the gun had an extended magazine that is illegal in California.
"You just don't expect it to happen in Thousand Oaks".
President Donald Trump said in a tweet Thursday morning that he was "fully briefed" on the shooting.
Additional units, including SWAT personnel arrived on the scene minutes later and found 11 victims and the deceased gunman.