Zayd bin Wahb narrates: Once we were sitting around Sayyiduna Hudhayfah (may Allah be pleased with him), when he said: What will your state be when the household of your Prophet split into two groups and come out, and begin to kill one another with the sword? We asked: O Abu Abdullah! Will that really happen? Then one of his companions asked: O Abu Abdullah! If we live to see that time, what should we do? He said: Look for the group that calls to (the cause of) Sayyiduna Ali (may Allah be pleased with him), and stay with that group, for that group will be upon guidance.
Al-Bazzar recorded it, and its narrators are thiqat (trustworthy).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب الفتن - أعاذنا الله منها / 12032