Police are investigating a "flash mob" robbery that occurred at the Westfield Topanga Shopping Center in Canoga Park. #LosAngelesPoliceDepartment said anywhere between 20 and 50 suspects flooded the mall's Nordstrom store a little after 4 p.m., ransacking shelves and displays for anything they could grab before fleeing. 👀 SWIPE via kcalnews •aintyoumalcom