The Public Prosecution office in Damanhour, Beheira on Tuesday launched investigations into the alleged killing of 12 prisoners by security men at Damanhour's general prison last month.
Al-Abadeyya Prison in Damanhour saw incidents of violence at the end of February which led to the deaths of 12 people and the injury of 16 others.
The prosecution on Tuesday heard the testimonies of the families of the prisoners who were killed in the violence.
The injured victims and the families of the dead have formally accused the prison's investigation head Sami Zaitoun and investigator Khaled Abdel Hadi of being behind a decision to open fire at the prisoners.
The injured victims said officers ordered that prison cells be opened and then started firing at prisoners once they started to escape.
A statement by the Interior Ministry had provided a different account of the incident, claiming that prisoners broke open the doors of their cells, forcing officers to shoot at them.