Musannaf Ibn Abi Shaybah

Hazrat Bishr bin Shaghaf narrates that Hazrat Abdullah bin Salam asked me about the Khawarij, so I replied that they are the ones who pray the longest prayers and fast the most. But when they cross the bridge, they shed blood and seize wealth. He said that you will be asked this same question about them. I told him not to martyr Hazrat Uthman, to leave him alone. By Allah, if you leave him for eleven nights, he will pass away on his bed. But they did not do so. When a prophet is killed, seventy thousand people are killed in retribution, and when a caliph is killed, thirty-five thousand people are killed in retribution.