Just before midnight on Wednesday, a gunman walked into Borderline Bar & Grill in Thousand Oaks, California and opened fire at more than 100 patrons who were there for a college country music night.

"All I remember was standing there with my friend and I heard the shots," recalled Sarah Rose DeSon, who was celebrating a friend's birthday at the popular music venue. "I'm pretty sure I saw him. I'll never get that picture out of my head. We dropped, heard gunshots, a lot of gunshots.

"Everyone was under the table so it was hard to get under there. By the grace of God I got to the front door."

DeSon was able to escape and so did her friend, who was found hiding in the bushes.

While these two were able to make it out of the bar, not everyone was so lucky.

The Ventura County Sheriff Geoff Dean confirmed that there have been 12 fatalities as well as "multiple victims of different levels of injuries."

Among those killed was a police officer, Deputy Ron Helus, a 29-year veteran who was one of the first to respond to the gunshot reports.

Witnesses reported that they saw a lot of smoke, which led them to believe that the gunman may have had smoke grenades.

Many people were forced to break through windows in order to run for their lives.

This incident brought back painful memories of another horrific mass shooting that took place during the Route 91 Harvest Festival in Las Vegas last October. A lone gunman opened fire from the 32nd floor of the Mandalay Bay hotel, leaving more than 200 injured and 59 dead.

According to the Los Angeles Times, some of the survivors of the Las Vegas shooting were reportedly in the bar last night.

"A lot of people in the Route 91 situation go here," said Charlie Gunn, 23, whose friend works at the Borderline Bar & Grill and was also at Route 91. "There's people that live a whole lifetime without seeing this, and then there's people that have seen it twice."

Josh Coaly, 27, and his friends, including one who survived the Vegas shooting, are regulars at the bar, but they were lucky to escape yesterday's shooting unscathed.

24-year-old Carl Edgar, who frequents the bar, also told The Times that about 20 of friends were inside when the shots were fired. While he hasn't been able to reach all of them, he's "not gonna get too worried," because he believes they're all safe.

"A lot of my friends survived Route 91," he said. "If they survived that, they'll survive this."

The shooter, who has not been identified, was found dead when the officers arrived at the scene. For now, his motives remain unclear, and authorities have "no idea" whether he has links to terrorism. Police are also unsure if he took his own life.

The Ventura Co. Sherrif's Department has set up a hotline for those who need assistance locating their loved ones.

President Donald Trump has been briefed on the shooting, and he released a statement on Twitter this morning.

"I have been fully briefed on the terrible shooting in California. Law Enforcement and First Responders, together with the FBI, are on scene. 13 people, at this time, have been reported dead. Likewise, the shooter is dead, along with the first police officer to enter the bar.

Great bravery shown by police. California Highway Patrol was on scene within 3 minutes, with first officer to enter shot numerous times. That Sheriff's Sergeant died in the hospital. God bless all of the victims and families of the victims. Thank you to Law Enforcement."

Our thoughts and prayers go out to those who have been affected by this horrible act.