This afternoon, Twitter blew up with reports of armed men taking over a rooftop in downtown. "Police just bullhorned that everyone on Spring street should find cover inside." And then the LAPD marched in. Via ABC7: "The suspects disappeared and officers discovered the weapons were plastic toy guns...The four individuals were not located. They are believed to be juveniles." [ABC7] UPDATE: LAT calls the weapons "air guns"; and blogdowntown calls them "air rifles."