Musnad Abu Ya'la al-Mawsili 129:154

Zuhayr narrated to us, Affan narrated to us, Hammad narrated to us, Qatadah, Humayd, and Thabit informed us, from Anas: That some people from Uraynah came to Medina and found its climate unsuitable. The Messenger of Allah (may Allah bless him and grant him peace) sent them to the camels of the Sadaqah and said, "Drink their urine and their milk." They killed the shepherd of the Messenger of Allah (may Allah bless him and grant him peace), drove away the camels, and apostatized from Islam. The Prophet (may Allah bless him and grant him peace) was informed about them, so he cut off their hands and feet from opposite sides, branded their eyes, and cast them into the Harrah. Anas said: I used to see one of them biting the earth with his mouth until they died. And sometimes Hammad would say: Biting the earth with his mouth until they died.