Task: Classify the mental state of the tweeter based on the tweet, determining if it is 'neutral or no emotion' or characterized by any of the provided emotions (anger, anticipation, disgust, fear, joy, love, optimism, pessimism, sadness, surprise, trust).
Tweet: @DSWT I despair at this madness! It's beyond #shocking it's cold blooded murder!  How long will #SouthAfrica stand by &amp;watch #WorldRhinoDay
This tweet contains emotions: 
anger, disgust, sadness, surprise