Here's what we know so far from Fox News

At least 12 people were killed late Wednesday night when a gunman opened fire at a nightclub in Thousand Oaks, Calif., police said.

Hundreds of people were inside the Borderline Bar & Grill for "college country night." Shots rang out at around 11:20 p.m., Ventura County police said. Witnesses inside said patrons used chairs to break windows in an attempt to escape the gunfire.

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