Musnad Ahmad Hadith 6926

Abdullah bin Harith says that when Amir Muawiyah (may Allah be pleased with him) was returning after the Battle of Siffin, I was walking between him and Amr bin Aas (may Allah be pleased with him). Abdullah bin Amr (may Allah be pleased with him) said to his father, "Father, did you hear the Prophet Muhammad (ﷺ) say about Ammar (may Allah be pleased with him): 'Alas! O son of Sumayyah, a rebellious group will kill you'?" Amr (may Allah be pleased with him) said to Amir Muawiyah (may Allah be pleased with him), "Are you listening to what he is saying?" Amir Muawiyah (may Allah be pleased with him) said, "You always bring such disturbing news. Did we martyr him? He was martyred by those who brought him (to the battlefield)."