Aslam narrates: I set out on a journey. When I returned, Sayyiduna Umar (may Allah be pleased with him) asked: "Whom were you with?" I said: "I was with a man from the tribe of Bakr bin Wa'il." Sayyiduna Umar (may Allah be pleased with him) said: "Did you not hear the Prophet (peace and blessings be upon him) say: 'Your brother is a Bakri (that is, one belonging to the tribe of Bakr), and you are not safe from him'?"
Al-Tabarani recorded it in al-Mu'jam al-Awsat via Zayd bin Abd al-Rahman bin Zayd bin Aslam from his father, and both of them are da'if (weak).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الحج / 5308