By Joe Sterling, Faith Karimi and Mohammed Tawfeeq CNN

(CNN) -- Bombs targeted two Coptic churches in Egypt as the Christian faithful observed Palm Sunday, one of the most important day on the religion's calendar.

A powerful blast rippled through a Palm Sunday service at a Coptic Christian church in the northern Egyptian city of Tanta, killing 25 people and wounding 60 others, state TV reported. The explosive device at St. George Coptic church in Tanta was planted under a seat in the church, where it detonated in the main prayer hall, it said.

At least 11 have been killed and 33 others wounded in a suicide bomb attack outside the Saint Mark Coptic Orthodox Cathedral in Alexandria according to two state-news outlets. Egyptian state media also reports that the head of Egypt's Coptic Church Pope Tawadros II was inside the Church when the blast happened.

There were no immediate claims of responsibility.

Palm Sunday is the Sunday before Easter, and 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.

In Tanta, news footage shows people gathered 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.

Social media video showed crowds gathered outside the church shortly after the attack.

There were no further details about the Alexandria incident. The city sits on the Mediterranean and has a large Christian population.

While it's unclear who attacked the church Sunday, Copts face persecution and discrimination that has spiked since the toppling of Hosni Mubarak's regime in 2011.

Dozens have been killed in sectarian clashes. 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 attack comes days after President Donald Trump welcomed Egyptian President Abdel Fattah el-Sisi to Washington and stressed his support for Cairo. Among the topics of mutual concern were terrorism and terror group ISIS.

El-Sisi met Saturday with a US congressional delegation led by US Rep. Darrell Issa, the Egyptian government said.

The meeting addressed Egypt's counter-terrorism efforts and adopting a strategy to fight terror and encourage religious tolerance and acceptance of others.

The Tanta attack Sunday drew outrage from religious leaders across the globe.

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.

"To my dear brother his Holiness Pope Tawadros II, to the Coptic church and to all of the dear country Egypt, I express my deep condolences, I prayed for the dead and the wounded, I am close to the families and to the entire community. God convert the hearts of the people who spread terror, violence and dead, and also the heart of who produces and traffic weapons," the pope said.

The Archbishop of Canterbury, serving the Church of England and the worldwide Anglican Communion, called the attacks "evil" and urged people to pray for the victims.

CNN's Sarah Sirgany and Bijan Hosseini contributed to this report

The-CNN-Wire
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