Musnad Ahmad 30:3661

Wahb narrated to us, my father narrated to us, he said: I heard Yunus narrating from al-Zuhri, from Humayd ibn Abd al-Rahman, that Abu Hurayrah said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "Time will draw near, wealth will overflow, tribulations will appear, and *al-harj* will increase." They said: "And what is *al-harj*, O Messenger of Allah?" He said: "Killing, killing."