Sayyiduna Usamah bin Sharik (may Allah be pleased with him) said: The Messenger of Allah (peace and blessings be upon him) said: "Any man who goes out to cause division in my Ummah, strike his neck."
Zayd bin Ata' bin al-Sa'ib narrated this hadith in this way from Ziyad bin Ilaqah, from Usamah, whereas the correct version is from Sayyiduna Arfajah (may Allah be pleased with him); and Muhammad bin Bishr likewise narrated it from Mujalid.
Hadith Referenceالمعجم الكبير للطبراني / باب الألف / 484