Musnad Ahmad 9:9

Yahya narrated to us, from Hisham, and Ibn Numayr, [who said] Hisham narrated to us, my father narrated to me, from Sa’id ibn Zayd ibn ‘Amr, from the Prophet (peace and blessings of Allah be upon him)—Ibn Numayr said: I heard the Messenger of Allah (peace and blessings of Allah be upon him)—he said: "Whoever takes a span of land unjustly, it will be collared around his neck on the Day of Resurrection down to the seven earths." Ibn Numayr said: "From the seven earths."