The Book of Pilgrimage (Kitab Al-Hajj)
Muslim :: Book 7 : Hadith 3155
'Amir b. Sa'd b. Abu Waqqas reported on the authority of his father (Allah be pleased with him) that Allah's Messenger (may peace be upon him) said, and then the (above-mentioned) hadith was narrated with this addition:" None should nurse ill-will towards the people of Medina, or Allah will melt him in fire like the melting of lead or the dissolution of salt in water.