According to the criminal court: https://www.icc-cpi.int/sites/default/files/RS-Eng.pdf
Article 6 on genocide: (c) Deliberately inflicting on the group conditions of life calculated to bring about its physical destruction in whole or in part;
This includes forcing them to leave their homes or denying them food.
But if, in addition to expelling them from their homes, you bomb the camps where they take refuge, as happened in Bureijbomb the camps where they take refuge, as happened in Bureij, killing civilians, then there is no longer any doubt.