Musannaf Ibn Abi Shayba 36:425

Waki’ narrated to us, from Sa’id ibn al-Sa’ib, who said: I heard an old man from Banu ‘Amir, one of the Banu Sawa’ah, who was called ‘Ubayd Allah ibn Ma’iyyah, say: Two men were struck [killed] on the day of al-Ta’if. He said: They were carried to the Prophet, peace and blessings of Allah be upon him. He said: He was informed about them, so he ordered that they be buried where they were struck.