Go and strike his neck. 'Ali came to him and he found him in a well making his body cool. 'Ali said to him: Come out, and as he took hold of his hand and brought him out, he found that his sexual organ had been cut. Hadrat 'Ali refrained from striking his neck. He came to Allah's Apostle ﷺ and said: Messenger of Allah, he has not even the sexual organ with him. (Using translation from Muslim 2771)
أَنَّ رَجُلًا كَانَ يُتَّهَمُ بِأُمِّ إِبْرَاهِيمَ وَلَدِ رَسُولِ اللَّهِ ﷺ فَقَالَ رَسُولُ اللَّهِ ﷺ لِعَلِيٍّ «اذْهَبْ فَاضْرِبْ عُنُقَهُ» فَأَتَاهُ عَلِيٌّ فَإِذَا هُوَ فِي رَكِيٍّ يَتَبَرَّدُ فِيهَا فَقَالَ لَهُ عَلِيٌّ اخْرُجْ فَنَاوَلَهُ يَدَهُ فَأَخْرَجَهُ فَإِذَا هُوَ مَجْبُوبٌ لَيْسَ لَهُ ذَكَرٌ