Musnad Ahmad 30:3245

Bahz narrated to us, he said: Sulaym ibn Hayyan narrated to me, he said: I do not know this except as my father narrated it to us and I read it to him, he said: I heard Abu Hurayrah saying—and I do not know it except from the Prophet, may Allah bless him and grant him peace—he said: "Indeed, before the Hour, there will be al-harj." It was said: "And what is al-harj?" He said: "Killing."