I was riding alongside Muawiya as he was returning from Siffin, positioned between him and Amr bin As.Abdullah bin Amr bin As said, "Father, did you not hear the Messenger of Allah ﷺ say to Ammar, 'Woe to you, son of Sumayy, the rebellious faction will kill you'?"Amr said to Muawiya, "Do you not hear what this man is saying?"Muawiya replied, "You keep bringing us trouble. Did we kill him? He was killed only by those who brought him out to battle."
إني لأسير مع معاوية في منصرفه من صفين، بينه وبين عمرو بن العاص، قال: فقال عبد الله بن عمرو بن العاص: يا أبت ما سمعت رسول الله ﷺ يقول لعمار: ويحك يا ابن سمية، تقتلك الفئة الباغية، قال: فقال عمرو لمعاوية: ألا تسمع ما يقول هذا؟ فقال معاوية: لا تزال تأتينا بهنة، أنحن قتلناه؟ إنما قتله الذين جاءوا به.
Ahmad narrated it (6499, 6500), and Nasai in Khasais Ali (167, 168), both by way of Amash, from Abdul-Rahman bin Ziyad, from Abdullah bin Harith, who related it. Its chain is sahih. Abdul-Rahman bin Ziyad, also said to be Ibn Abu Ziyad, the freedman of Banu Hashim, is trustworthy. Ibn Main and Ajli both affirmed his trustworthiness, as mentioned in Tahdheeb, and Ibn Hibban listed him among al-Thiqat. Abdullah bin Harith is Ibn Nawfal, who had seen the Prophet.As for Muawiya's statement, "The ones who killed him are those who brought him," this is an interpretation of the hadith, a departure from its apparent meaning. And his word "al-hanah" is a euphemism for something reprehensible, an ugly deed.