I merely copied and pasted the first piece of news I found.
https://edition.cnn.com/us/live-news...ntl/index.html
"The county sheriff, Geoff Dean, identified the gunman as 28-year-old Ian David Long of Newbury Park, Calif., who had served in the Marine Corps. Mr. Long apparently took his own life after being confronted in the bar, the sheriff said. The .45-caliber handgun was purchased legally, but had been outfitted with an extended magazine."
I don't spend all day online..