SAN FRANCISCO (KGO) -- As details continue to emerge about the mass shooting, authorities are looking for early warning signs that might've been missed. It seems the new battle cry in the war on terror is: "If you see something, say something." And in the Bay Area, there's an app for that. Click here to learn more about the BART Watch app here.
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BART app lets passengers silently text police, send photos
SAN BERNARDINO MASS SHOOTING