Bukhari :: Book 3 :: Volume 43 :: Hadith 624
Narrated Anas:
Allah's Apostle said, "Help your brother, whether he is an oppressor or he is an oppressed one. People asked, "O Allah's Apostle! It is all right to help him if he is oppressed, but how should we help him if he is an oppressor?" The Prophet said, "By preventing him from oppressing others."
Bukhari :: Book 3 :: Volume 43 :: Hadith 629
Narrated Abu Huraira:
Allah's Apostle said, "Whoever has oppressed another person concerning his reputation or anything else, he should beg him to forgive him before the Day of Resurrection when there will be no money (to compensate for wrong deeds), but if he has good deeds, those good deeds will be taken from him according to his oppression which he has done, and if he has no good deeds, the sins of the oppressed person will be loaded on him."
Bukhari :: Book 3 :: Volume 43 :: Hadith 623
Narrated Anas bin Malik:
Allah's Apostle said, "Help your brother, whether he is an oppressor or he is an oppressed one."