Sunan Ibn Majah, Book 36, Hadith 126 (In-Book) ⓘ
It was narrated from Abu Musa that the Messenger of Allah said: “After you days will come when ignorance will become widespread, knowledge will disappear and there will be much Harj.” They said: “O Messenger of Allah, what is Harj?” He said: “Killing.”
حَدَّثَنَا مُحَمَّدُ بْنُ عَبْدِ اللَّهِ بْنِ نُمَيْرٍ، وَعَلِيُّ بْنُ مُحَمَّدٍ، قَالاَ حَدَّثَنَا أَبُو مُعَاوِيَةَ، عَنِ الأَعْمَشِ، عَنْ شَقِيقٍ، عَنْ أَبِي مُوسَى، قَالَ قَالَ رَسُولُ اللَّهِ ـ صلى الله عليه وسلم ـ " إِنَّ مِنْ وَرَائِكُمْ أَيَّامًا يَنْزِلُ فِيهَا الْجَهْلُ وَيُرْفَعُ فِيهَا الْعِلْمُ وَيَكْثُرُ فِيهَا الْهَرْجُ " . قَالُوا يَا رَسُولَ اللَّهِ وَمَا الْهَرْجُ قَالَ " الْقَتْلُ " .
also referenced under: Hadith 4051 (Reference) & Volume 5, Book 36, Hadith 4051 (DarusSalam)