Sayyiduna Anas (may Allah be pleased with him) narrates from the Noble Prophet (peace and blessings be upon him) that  the Prophet (peace and blessings be upon him) said: "Medina is a sanctuary from here (Mount ‘Ir) to there (Thawr); its trees should not be cut, nor should any oppression or innovation be committed here. Whoever invents any act of oppression or innovation here, upon him is the curse of Allah, the angels, and all people (and in one narration: whoever gives shelter to an innovator, upon him as well)."