What's the difference between a "Flying Squad" and a "flashmob"? Either way it was a planned, organized and coordinated assault.
“Flying squads” were used often in the 20th century by police and unions. With unions, they are pre-determined groups of individuals who are “on call” to take whatever actions may be required of them wherever needed.
Flash mobs require communications to spread geometricly among unrelated individuals and may or may not come to fruition.
I realize that “Flying Squad” may not sound as hip as “Flash Mob”, but it is what it is. Flying squads were named and used long before the first flash mob was ever dreamed of.