Maliks Muwatta Book 54, Hadith Number 29.
Section : Concerning the East.
Malik related to me from Abdullah ibn Dinar that Abdullah ibn Umar said, “I saw the Messenger of Allah, may Allah bless him and grant him peace, pointing at the east and saying, ‘The cause of dissension is here. The cause of dissension is here, from where the helpers of shaytan arise.'”