By Joe Sterling, Faith Karimi, Mohammed Tawfeeq and Hamdi Alkhshali
(CNN) — ISIS claimed responsibility for bombings that killed 43 at two Coptic churches in Egypt on Palm Sunday — brazen strikes against a vulnerable minority on one of the most important days on the Christian calendar.
ISIS issued the claim on the Telegram messaging platform. The claim was circulated by several ISIS supporters. ISIS identified the suicide bombers as Egyptian nationals. Egyptian authorities have not confirmed the bombers’ nationalities.
In their claim of responsibility, ISIS warned of more attacks with this message: “The Crusaders and their tails from the apostates must be aware that the bill between us and them is very large and they will be paying it like a river of blood from their sons, if God willing.”
The first blast was in the northern city of Tanta, where a powerful explosion ripped through a Palm Sunday service at St. George’s Church, killing 27 people and wounding 78 others, state TV reported. The explosive device was planted under a seat in the main prayer hall, it said.
Not long after that, at least 16 people were killed and 41 others wounded in a suicide bomb attack outside St. Mark’s Coptic Orthodox Cathedral in Alexandria, according to two state-news outlets. Egyptian state media also reported that the head of Egypt’s Coptic Church, Pope Tawadros II, was inside the cathedral when the blast happened. He was not injured.
In a statement, Egyptian President Abdel Fattah el-Sisi condemned the attacks, saying the “outrageous” action “targets both the Copts and Muslims of the homeland.” He ordered investigators to “hunt down the perpetrators” and “take all measures to offer the necessary care for the wounded.”
He called an urgent meeting of his country’s National Defense Council and declared three days of nationwide mourning.
“The attack will not undermine the resolve and true will of the Egyptian people to counter the forces of evil, but will only harden their determination to move forward on their trajectory to realize security, stability and comprehensive development,” the statement said.
United Nations Secretary-General António Guterres also condemned the attacks and offered his sympathies to the victims and to the country in statement through a spokesman.
Guterres “wishes a quick recovery to those injured and hopes that the perpetrators of this horrific terrorist act will be swiftly identified and brought to justice,” the spokesman, Stéphane Dujarric, said.
The US State Department, in a statement, also issued a rebuke, calling the bombings “barbaric attacks on Christian places of worship.”
“The United States will continue to support Egypt’s security and stability in its efforts to defeat terrorism,” said acting spokesperson Mark Toner.
The horrific attacks were the latest against Christians in the region, this time on Palm Sunday — the Sunday before Easter, and the day that marks the start of Holy Week for Christians.
Nile and Masriya TV, Egyptian state outlets, aired black banners in the upper left of its newscasts to signify mourning for the victims of both explosions.
News footage from Tanta shows people gathering at the church, singing hymns. The video then quickly switches to bars as harrowing screams and cries echo in the background.
“Everything is destroyed inside the church” and blood can be seen on marble pillars, said Peter Kamel, who saw the aftermath of the carnage.
It appeared the explosive device was placed near the altar, he said. Priests and the church choir were among the casualties.
In Alexandria, the Interior Ministry said in a statement that police assigned to St. Mark’s stopped a terrorist with an explosive belt from breaking into the church. Along with civilians, a policeman, a policewoman and other police staff were killed.
Egyptian blogger Maged Butter told CNN he saw five or six ambulances and blood stains 100 meters away from the site of the explosion — which happened near the church gate.
He said women were crying and looking for their loved ones and were yelling at police for “not protecting” them.
“Every now and then, I see a person crying — I think they are Christian — and they keep saying: ‘have you seen my family? Have you seen my family?’ ” Butter said.
Fadi Sami, another witness, was inside the Alexandria cathedral when he heard about the church bombing in Tanta, when the Coptic pope was leading the prayers for Palm Sunday.
And even though no one announced the Tanta news, Sami said he could hear the sadness in the pope’s voice. He left as the pope finished the sermon. Twenty minutes later, a suicide bomber blew himself up at the gate of the church.
“I came back and the area was covered in smoke. The stores around the church were all destroyed,” he said. “There were bodies and body parts everywhere, outside and inside the gate. I saw a man put together what was left of his son in a bag.”
Alexandria sits on the Mediterranean and has a large Christian population. Downtown is usually busy but was relatively quiet on Sunday because of the holiday. “This is usually a very busy area, but thank God it is a Sunday, and many shops are closed,” he said.
Copts in Egypt have faced persecution and discrimination that has spiked since the toppling of Hosni Mubarak’s regime in 2011.
Dozens have been killed in sectarian violence. In December, an attack at a Coptic church in Cairo killed 25 people.
Coptic churches and homes have been set on fire, members of the Coptic minority have been physically attacked, and their property has been looted, rights group Amnesty International reported in March.
Coptic Christians make up about 10% of Egypt’s population of 91 million. They base their theology on the teachings of the apostle Mark, who introduced Christianity to Egypt. Tanta is roughly 60 miles (96 kilometers) north of Cairo, in the Nile delta.
The bombings come days after President Donald Trump welcomed el-Sisi to Washington and stressed his support for Egypt. Among the topics of mutual concern were terrorism and ISIS. Trump tweeted a condemnation of Sunday’s attacks and said he has “great confidence el-Sisi will handle the situation properly.”
El-Sisi met Saturday with a US congressional delegation led by US Rep. Darrell Issa, the Egyptian government said. The meeting addressed Egypt’s counterterrorism efforts and a strategy to fight terror while encouraging religious tolerance and acceptance of others.
Pope Francis is scheduled to visit Cairo this month, where he will meet with various religious leaders, including the head of the Coptic Orthodox Church. He expressed his grief following the church attack.
The Archbishop of Canterbury, Justin Welby, called the attacks “evil” and urged people to pray for the victims. Russia’s President Vladimir Putin condemned the attack and offered his condolences to el-Sisi, according to Russia’s state-run Tass.
CNN’s Sarah Sirgany, Tamara Qiblawi, Bijan Hosseini, Ian Lee and Darran Simon contributed to this report
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