Musannaf Ibn Abi Shayba 36:330

Ja'far ibn 'Awn narrated to us, he said: Ibrahim ibn Isma'il al-Ansari informed us, from al-Zuhri, he said: 'Amr or 'Umar ibn Usayd informed me, from Abu Hurayrah, that the Messenger of Allah (may Allah bless him and grant him peace) sent ten men as a reconnaissance unit (sariyyah) and appointed 'Asim ibn Thabit as their leader. They went out until, when they were at al-Hada, they were mentioned to a clan of Hudhayl called Banu Lihyan. So they sent one hundred archers against them. They found the place where they had eaten dates and said, "These are the date pits of Yathrib." Then they followed their tracks until, when 'Asim and his companions sensed them, they took refuge on a mountain. The others surrounded them and called them down, offering them a covenant. 'Asim said, "By Allah, I will not come down under the covenant of a disbeliever. O Allah, inform Your Prophet about us." Then Ibn Dathinah al-Bayadi came down to them.