Jihad (Kitab Al-Jihad)
Dawud :: Book 14 : Hadith 2639
Narrated Jarir ibn Abdullah:
The Apostle of Allah (peace_be_upon_him) sent an expedition to Khath'am. Some people sought protection by having recourse to prostration, and were hastily killed. When the Prophet (peace_be_upon_him) heard that, he ordered half the blood-wit to be paid for them, saying: I am not responsible for any Muslim who stays among polytheists. They asked: Why, Apostle of Allah? He said: Their fires should not be visible to one another.