ISIS lays claim to Coptic church bombing in Cairo

The Islamic State has claimed responsibility for the bombing of a Coptic Cathedral that resulted in the deaths of 25 people on Sunday.

Egyptian authorities have identified the suicide bomber who carried out the attack on St. Mark's Coptic Orthodox Cathedral as Mahmoud Shafik Mohamed Mostafa, but ISIS used the pseudonym Abu Abdallah al-Masri, according to The New York Times.

A surveillance video released by the authorities showed a figure believed to be Mostafa entering the church just before the explosion. It was reportedly the deadliest attack on Egyptian civilians in years and the worst act of sectarian violence since the bombing of a Coptic church in Alexandria in 2011.

Egyptian President Abdel Fattah el-Sisi has previously blamed most of the attacks on the Muslim Brotherhood, whose leader, Mohamed Morsi, was deposed is 2013.

The Interior Ministry stated on Monday that exiled leaders of the Brotherhood provided "financial and logistical support" for the assault. The Brotherhood, however, condemned the bombing, and militancy experts have said that it was unlikely that the organization would have financed an ISIS operation.

Sisi stated that three men and one woman were arrested in connection with the attack, but other suspects are still at large.

Mostafa reportedly was arrested at a Muslim Brotherhood protest in 2014. His family said that he was jailed but they lost contact with him when he was released later. His lawyer claimed that he was tortured while he was detained, which might have led to his radicalization.

Egyptian Copts have long been complaining about systematic discrimination to the government, but Sisi's administration chose to focus instead on its foreign critics.

Christians have accused the government of failing to protect them, but officials have pointed out the quick identification of the suspect as proof that the security bodies are efficient.

However, Christian activist Nader Shokry believes that the government could have done more to prevent the bombing.

"How did all this planning take place without the security knowing about it?" Shokry said, according to Mail Online.

"You are saying that this person belongs to a terror group and has been previously arrested... So you should have kept a close eye on him," he added.