An attack on a bus carrying Christian pilgrims in Egypt on Friday killed at least 28 people, including children, and injured at least 22 more.

The AP reported that, according to the Egyptian government, the bus was stopped and attacked by gunmen in the desert south of Cairo, en route to St. Samuel the Confessor monastery in Minya, Egypt. Witnesses reported seeing eight to 10 gunmen wearing masks and military uniforms, who fired on the bus.

Bishop Angaelos, general bishop of the Coptic Orthodox Church of the UK, tweeted on Friday that he had spoken to the Bishop of Menia, and confirmed the attack.

The May 26 attack is the latest in a string of violent incidents where Coptic Christians in Egypt have been targeted. Twenty-nine were killed when a chapel adjacent to St. Mark's Coptic Orthodox Cathedral in Cairo was bombed in December.

The Islamic State released a threatening video message after that attack, saying, "Oh crusaders in Egypt, this attack that struck you in your temple is just the first with many more to come, God willing."

Later in the winter, several more were killed in a series of murders in Egypt's Sinai region, and ISIS affiliates there claimed responsibility. Hundreds fled their homes in the face of the violence.

Then on Palm Sunday, 45 were killed in two separate attacks on Masses: A bomb was detonated inside St. George's Coptic Orthodox Church in Tanta, which killed 28, while a suicide bomber detonated outside of St. Mark's Coptic Orthodox Cathedral in Alexandria – where the Patriarch of Alexandria Pope Tawadros II was saying Mass – killed 17 including himself.

Egypt's president Abdul Fattah el-Sisi declared a three-month state of emergency following the April 9 attacks, and Friday's attack fell within the time frame.

A checkpoint near St. Catherine's monastery in the Sinai region was also attacked in April, resulting in one dead and four injured. ISIS claimed responsibility for that attack.

Church leaders offered prayers following the May 26 attack.

A Vatican telegram offered the condolences of Pope Francis.

"Deeply saddened to learn of the barbaric attack in central Egypt and of the tragic loss of life and injury caused by this senseless act of hatred, Pope Francis expresses his heartfelt solidarity with all those affected by this violent outrage," the telegram said.  

"He assures their grieving families and all who have been injured of his ardent prayers, and he pledges his continued intercession for peace and reconciliation throughout the nation."

Bishop Michael F. Burbidge of Arlington, Va. said in a statement that he is once again "deeply saddened by news of violence against innocent people of faith."

"This attack reminds us again of the horrific persecution of our Christian brothers and sisters in the Middle East and their courageous witness to their faith," he continued. "I ask that all the faithful in the Diocese of Arlington and people of good will join me in prayer for the victims of today's attack."

He asked for the intercession of Mary, Queen of Peace, "for an end to violence and religious persecution throughout the world."

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Cardinal Donald W. Wuerl of Washington, D.C., blogged about the attacks, saying, "Our response to this most recent atrocity is to turn to our Lord Jesus Christ, whose eternal love triumphs over suffering and evil and turns the darkness of death into the dawn of new life."

"(W)e are all one human family. We are all in this together and we must all stand together in solidarity against such violence and evil," he said, stressing that while we may be tempted to think that our efforts at change are futile, "we can look for opportunities to speak out, to awaken consciences and urge a change of heart."

"At the very least, we can persevere in prayer," the cardinal said. "Let us pray for the gifts of the Spirit to strengthen us and also to touch the hearts of all to stop the violence and so that toleration and genuine peace reigns in every land."

Editor's note: Updated with reactions from Church leaders.