Authorities in Egypt have declared three days of national mourning for the victims of twin attacks on Coptic churches. The overall death toll has surpassed 40, and it's expected to rise. ISIL militants have claimed responsibility for both attacks. We begin our coverage tonight in Tanta, where the first blast took place. More than 25 people are dead. CGTN's Yasser Hakim is at the scene of the blast, and filed this report.