Musnad Ahmad 33:1116

Hassan narrated to us, Ibn Lahi'ah narrated to us, Abu al-Zubayr informed us, he said: And Jabir informed me that he heard the Messenger of Allah, peace and blessings of Allah be upon him, saying: "The likeness of Medina is like the bellows; and the sanctuary of Ibrahim is Mecca, and I declare Medina a sanctuary. It is like Mecca; what is between its two lava fields is sacred, and all of its protected land. No tree shall be cut from it, except that a man may feed his livestock from it. And the plague shall not approach it—if Allah wills—nor shall the Dajjal. And the angels guard it at its mountain passes and its gates." He said: And I heard the Messenger of Allah, peace and blessings of Allah be upon him, saying: "And it is not lawful for anyone to carry a weapon in it for fighting."