From Sahih Muslim (Hadith 6417):
Anas reported that Allah's Messenger (ﷺ) saw children and women of the Ansar coming back from a wedding feast. Allah's Apostle (ﷺ) stood up motionless (as a mark of respect) and said:O Allah, (bear witness) (and addressing the Ansar), said: You are dearest to me amongst people, (and said: O Allah (bear witness) (and addressing the Ansar), said: You are dearest to me amongst people. And he meant Ansar
Reference: Muslim 6417