Sahih al-Bukhari, Hadith 6935 ⓘ
Narrated Abu Huraira: Allah's Messenger said, "The Hour will not be established till two (huge) groups fight against each other, their claim being one and the same."
حَدَّثَنَا عَلِيٌّ، حَدَّثَنَا سُفْيَانُ، حَدَّثَنَا أَبُو الزِّنَادِ، عَنِ الأَعْرَجِ، عَنْ أَبِي هُرَيْرَةَ ـ رضى الله عنه ـ قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " لاَ تَقُومُ السَّاعَةُ حَتَّى تَقْتَتِلَ فِئَتَانِ دَعْوَاهُمَا وَاحِدَةٌ " .
also referenced under: Book 88, Hadith 17 (In-Book) & Volume 9, Book 84, Hadith 69 (USC-MSA)