It is narrated from Sayyiduna Imran bin Husayn and Sayyiduna Samurah bin Jundub (may Allah be pleased with them both) that a man freed six of his slaves at the time of his death, and he had no wealth other than them. So the Prophet (peace and blessings be upon him) cast lots between them, freed two, and kept four in slavery.
Hadith Referenceالمعجم الكبير للطبراني / باب السين / 6913