Musnad Ahmad 337:2

'Affan narrated to us, he said: Hammad—meaning Ibn Salamah—narrated to us, from Yahya ibn Sa'id, from Muslim ibn Abi Maryam, from 'Ata' ibn Yasar, from al-Sa'ib ibn Khallad, that the Messenger of Allah (may Allah bless him and grant him peace) said: "Whoever frightens the people of Medina, Allah the Almighty will frighten him, and upon him is the curse of Allah, the angels, and all of mankind. Allah will not accept from him on the Day of Resurrection any obligatory or supererogatory deed."