A mass shooting at a Southern California bar and country music venue overnight (November 7) has left twelve dead and many more wounded. One of those killed was Ventura County Sheriff's Sgt. Ron Helus, who rushed into the building when police arrived at the scene. The establishment was crowded with more than 100 people, including many college students, Ventura County Sheriff Geoff Dean said in a press conference.

On Thursday (November 8), the gunman was identified as 28-year-old Ian David, a former Marine. The suspect reportedly turned the gun on himself and took his own life when confronted by police. While the .45-caliber handgun that David allegedly used was purchased legally, it had reportedly been outfitted with an extended magazine.

Today many celebrities are speaking out on social media about the shooting. Many are sending prayers and condolences, while also demanding more gun control and a serious discussion about gun violence in America.

"My heart is dust from being broken for so many places in our country so many times," actor and Broadway composer Lin-Manuel Miranda tweeted Thursday morning.

"Twelve people killed in the most deadly mass shooting in America...since last week," actress Yvette Nicole Brown shared.

See more reactions, below:

16 Celebrities Who Are Demanding Tighter Gun Control Laws

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