The Messenger of Allah ﷺ said, "Kill the elders of the polytheists and spare their youth."
قال رسول الله ﷺ: اقتلوا شيوخ المشركين واستبقوا شرخهم.
Abu Dawud (2670) narrated it from Saeed bin Mansur (and it is in his Sunan, 2624), he said, Hushaym narrated to us, he said, Hajjaj narrated to us, he said, Qatada narrated to us, from Hasan, from Samura, and he mentioned it. Its chain is hasan because of Hajjaj, who is Ibn Artah, for his hadith is hasan when he states clearly that he heard it directly, since he is a mudallis.Tirmidhi (1583) narrated it through another route, from Walid bin Muslim, from Saeed bin Bashir, from Qatada, with the same wording. Walid bin Muslim is a mudallis, and he narrated it using the ambiguous form "an", and Saeed bin Bashir is daif by consensus of the scholars of knowledge. Despite this, Tirmidhi said, "Hasan gharib." In one copy it reads, "Hasan sahih gharib." He also said, Hajjaj bin Artah narrated it from Qatada with similar wording. Perhaps he graded this route as sahih or hasan on account of Hajjaj corroborating him.As for Hasan, it has already been mentioned many times that he heard directly from Samura bin Jundab without restriction, and that he had a book from him, and Tirmidhi also leans toward this view.He said, "Ash-Sharkh" refers to young boys who have not yet grown facial hair. And his statement "the elders of the polytheists" means their chiefs and those who managed the affairs of war.