Transcript for Suicide bombings hit two Christian churches in Egypt

And we begin with a pair of suicide blasts targeting Christians at the start of holy week. One of the attackers seen on surveillance, detonating a suicide vest at a metal detector just outside a Christian church in historic Alexandria. And explosives tearing through a church in tanta, the aftermath at both scenes chilling. At least 44 killed, and more than 125 injured in the twin bombings. Tonight, the white house responding as ISIS claims responsibility. Alex Marquardt reporting tonight from the region. Reporter: On one of the holiest days of the year, this massive blast killing at least 17 at one of Alexandria's most famous cathedrals. Security cameras capturing this man, a suicide bomber, approaching the coptic church. Told to go to through a metal detector, he pauses next to two police officers and detonates his explosives. The coptic pope, the head of the church, had been inside, but escaped unharmed. That followed another suicide blast just hours earlier in the middle of palm Sunday mass in the city of tanta. The video feed cutting out as chaos erupts. Churchgoers frantically searching for survivors. "I got up, and saw bodies all around me," this man said. "I climbed onto the pews and got out using a side door, then I heard screams." All told, at least 44 were killed in the twin bombings and more than 125 wounded. ISIS soon claimed responsibility, and warned of more attacks to come on Egypt's Christians. Bloodied floors and shattered pews mixed with the shock, tears and screams of worshippers, giving way to anger at security forces. "The authorities have received warnings before that the church is being targeted," this man said. "Why weren't proper measures taken?" And Egypt's president sisi is hearing a lot of criticism about not guarding against the terror threat. Tonight, now declaring a three-month state of emergency. Reporter: Right, and that likely means a significant crackdown, in a country with rampant human rights abuses. We understand that just a short time ago, president Donald Trump did call president sisi to express his condolences. Alex, thank you. And president trump returning to the white house from mar-a-lago, his Syria air strikes front and center in the foreign policy debate. Inning -- infuriatiing Russia has

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