It is narrated from Sayyiduna Zayd bin Arqam (may Allah be pleased with him); he said: The leg of a wild ass was gifted to the Messenger of Allah (peace and blessings be upon him), and he (peace and blessings be upon him) said: "Convey my greetings of peace to him and tell him that had we not been in ihram, we would not have returned it."
Hadith Referenceالمعجم الكبير للطبراني / باب الزاي / 4947