Sayyiduna Sa'id bin Zayd (may Allah be pleased with him) says that the Messenger of Allah (peace and blessings be upon him) said: "Whoever wrongfully seizes a handspan of land, Allah will make him wear a collar of seven earths on the Day of Resurrection."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الغصب / 11532