The capture in the Danish/Swedish strait of Oresund of a fish some 20 centimeters in size and with long sharp teeth has caused Danish swimmers to leave the water fearing an invasion of meat-eating killer fish, Piranhas. There is, however, no cause for panic, say experts. The fish, though exotic, is a Pacu, not a piranha. Nonetheless, they caution male swimmers to protect their privates when swimming in the sound.