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Of the Khulefa of the Prophet Muhammad (saw) and the Promised Messiah (as), 4 were attacked by assassins. One survived. Name the 4 Khulefa who were attacked.
Who were Hadhrat Umar (ra), Hadhrat Uthman (ra), Hadhrat Ali (ra) (all died), and Hadhrat Mirza Bashiruddin Mahmud Ahmad (ra) (survived)?