Sheep have been attacked in a field belonging to Osney Lodge Farm, in Blindley Heath.
Three are dead and several others were left injured in the attack off Byers Lane.
Police have said that there are no witnesses to the actual attack which occurred before 7.30am yesterday (Tuesday).
But, someone may have seen a dog straying with blood on it, or aware of a neighbour's dog that has gone missing.
If you saw or heard anything, call PC Sarah Warner on 101 quoting reference number P13276931.
