KYIV, Ukraine — A series of explosions rocked Kyiv on Saturday morning and minutes later air raid sirens started to wail as an apparent missile attack on the Ukrainian capital was underway. Explosions were heard in the Dniprovskyi district, a residential area on the left bank of the Dnieper River, Kyiv mayor Vitali Klitschko said. The Ukrainian capital hasn’t been attacked with missiles since New Year’s night, Jan. 1.