People gather outside St. Peter and St. Paul Coptic Orthodox Church (L, foreground) that was targeted by a bombing, while the Coptic Cathedral is in the background, in Cairo, Egypt, on Dec. 11 2016.
The blast took place as the mass being held in the chapel was about to end and coincided with a national holiday in Egypt marking the birth of Islam's Prophet Muhammad.
Egyptian security forces and members of the clergy inspect the scene of the explosion.
Egypt's official MENA news agency said an assailant lobbed a bomb into a chapel close to the outer wall of St Mark's Cathedral.
A relative of one of the blast victims is comforted by a police officer.
The Egyptian Government has declared three days of mourning following the bombing.
Pieces from a damaged bench lie scattered inside St. Mark Cathedral.
Members of special police forces stand guard to secure the area around after the explosion.
An man shows small pieces of metal outside Saint Peter and Saint Paul Coptic Orthodox Church.
An Egyptian Coptic pope inspects damaged caused by the blast at St. Mark Cathedral.