Tell him that you are here to help him learn the skills of getting along with others. Have the child review rules for getting along with each other and treating people with respect. If he responds with a rationalization regarding what the other person did to him, tell him that he is always responsible for his actions no matter what was done to him. Remind the child that choosing to use his words and talk about what upsets him is always the best choice. This type of processing after misbehavior helps the child make better decisions for next time.
Error correction teaches self responsibility.
Review the rationale about mistakes being okay if you learn from them. That is why pencils have erasers. That is why we have word processing programs for computers with delete buttons. That is why we have U turns. The neat thing about making a mistake is the learning that you can gain from it.