حروب الردة
The Twelver Shia believe that Abu Bakr sent Khalid ibn Walid to crush those who were in favour of Ali's caliphate ("see Ridda wars"). The Twelver Shia strongly refute the idea that Abu Bakr or Umar were instrumental in the collection or preservation of the "Quran", claiming that they should have accepted the copy of the book in the possession of Ali.