Al-Qasas 28:15

Wadakhala almadeenata AAala heenighaflatin min ahliha fawajada feeha rajulayniyaqtatilani hatha min sheeAAatihi wahathamin AAaduwwihi fastaghathahu allathee minsheeAAatihi AAala allathee min AAaduwwihifawakazahu moosa faqada AAalayhi qala hathamin AAamali ashshaytani innahu AAaduwwun mudillunmubeen

And he entered the city at a time of inattention by its people and found therein two men fighting: one from his faction and one from among his enemy. And the one from his faction called for help to him against the one from his enemy, so Moses struck him and [unintentionally] killed him. [Moses] said, "This is from the work of Satan. Indeed, he is a manifest, misleading enemy."

Once he entered the city at a time when its people were heedless; so he found in it two men fighting each other: This one was from his own group, and that one from his enemies. So the one from his own group called him for help against the one who was from his enemies. So Mūsā gave him a blow with his fist and finished him off. (Then) He (Mūsā) said (out of remorse), “This is some of Satan’s act. He is indeed a clear enemy who misleads (people).”