Musnad Ahmad 907:161

Yahya ibn Sa'id narrated to us, from Shu'bah, Simak narrated to me, he said: I heard Jabir ibn Samurah saying: I heard the Messenger of Allah, peace and blessings of Allah be upon him, or he said: The Messenger of Allah, peace and blessings of Allah be upon him, said: "Indeed, before the Hour, there will be liars." My brother said: And he was closer to him than I was. He said: Did you hear it? He said: "So beware of them."