Turks Take to Streets For May Day ProtestsTurkish police put Istanbul under a security shutdown to prevent demonstrators from gaining unauthorized access to the iconic Taksim square.A masked protester runs away from a water cannon's jet during clashes with police in Okmeydani neighborhood in Istanbul.STRINGER/TURKEY / ReutersPrintMay 1, 2015, 5:47 PM UTC / Updated May 1, 2015, 6:01 PM UTC / Source: NBC News