Qur'an 28:15

وَدَخَلَ ٱلْمَدِينَةَ عَلَىٰ حِينِ غَفْلَةٍ مِّنْ أَهْلِهَا فَوَجَدَ فِيهَا رَجُلَيْنِ يَقْتَتِلَانِ هَـٰذَا مِن شِيعَتِهِۦ وَهَـٰذَا مِنْ عَدُوِّهِۦ ۖ فَٱسْتَغَـٰثَهُ ٱلَّذِى مِن شِيعَتِهِۦ عَلَى ٱلَّذِى مِنْ عَدُوِّهِۦ فَوَكَزَهُۥ مُوسَىٰ فَقَضَىٰ عَلَيْهِ ۖ قَالَ هَـٰذَا مِنْ عَمَلِ ٱلشَّيْطَـٰنِ ۖ إِنَّهُۥ عَدُوٌّ مُّضِلٌّ مُّبِينٌ

And he entered the city at a time of carelessness of its folk, and he found therein two men fighting, one of his own caste, and the other of his enemies; and he who was of his caste asked him for help against him who was of his enemies. So Moses struck him with his fist and killed him. He said: This is of the devil's doing. Lo! he is an enemy, a mere misleader.