The Book of Pilgrimage (Kitab Al-Hajj)

Muslim :: Book 7 : Hadith 3166

Abu Huraira (Allah be pleased with him) reported Allah's Apostle (may peace be upon him) as saying: Medina is a sacred territory, so he who made any innovation in it. or gave protection to an innovator, there is upon him the curse of Allah, that of the angels and that of all the people. There would not be accepted on the Day of Resurrection either obligatory acts or supererogatory acts from him.

Source materials are from the University of Southern California MSA site
Hadith eBooks converted from Imaan Star