We flush em away!
Viewed by Sunni clerics as little better than Jews. After the death of Mohammed there was a big power struggle to install his deputy or Kalifa ( from where we get the word caliph ). "The Shia I Ali" or Partisans of Ali backed Big Mo's son-in-law Ali for the job but got a good shoeing by the opposition.
The rift in Islam remains to this day although in the past there didn't seem to be a problem between the two groups. Guess when you start blowing up 'unbelievers' you just cant stop!
See religious wars