(24) باب مَنْ أَجَابَ الْفُتْيَا بِإِشَارَةِ الْيَدِ وَالرَّأْسِ
Narrated Abu Huraira:
The Prophet (ﷺ) said, "(Religious) knowledge will be taken away (by the death of religious scholars) ignorance (in religion) and afflictions will appear; and Harj will increase." It was asked, "What is Harj, O Allah's Messenger (ﷺ)?" He replied by beckoning with his hand indicating "killing." (Fath-al-Bari Page 192, Vol. 1)
Reference: Sahih al-Bukhari 85
In-book reference: Book 3, Hadith 27
USC-MSA web (English) reference(deprecated numbering scheme): Vol. 1, Book 3, Hadith 85