Sahih Bukhari Volume 3, Book 34, Hadith Number 274.

Narated By Jabir : While we were offering the prayer with the Prophet a caravan carrying food came from Sham. The people looked towards the caravan (and went to it) and only twelve persons remained with the Prophet. So, the Divine Inspiration came; “But when they see some bargain or some amusement, they disperse headlong to it.” (62.11)