Today on Inside Edition: Tamera Mowry-Housley's Niece Is Among California Victims; Who Was the Shooter?

Inside Edition has the latest on the California bar shooting.

As America reels from yet another mass shooting, Inside Edition is learning more about the 12 lives lost.

Among the victims of the California bar shooting was a veteran police sergeant planning to retire within the next year. Actress Tamera Mowry-Housley revealed her 18-year-old niece, Alaina Housley, was killed in the attack as well.

Also on today's show, we ask: Who was the shooter, and why did he carry out the attack?

The gunman reportedly threw smoke grenades into the crowd, adding to the chaos before opening fire. Would you know how to escape a smoke-filled room? Security experts shared their advice with Inside Edition.

For more Inside Edition stories, tune in to the show Thursday. Check here for local listings.