Explosion at Coptic Cathedral in Cairo kills 25

A bomb explosion in the main Coptic Cathedral in Cairo has killed at least 25 people and wounded 49 on Sunday.

Many of the victims were believed to be women and children who were attending the Sunday mass at a chapel adjoining St. Mark's cathedral, according to a report from BBC.

"I found bodies, many of them women, lying on the pews. It was a horrible scene," said Attiya Mahrous, who works at the cathedral.

"There were children. What have they done to deserve this? I wish I had died with them instead of seeing these scenes," said another witness.

Egyptian President Abdul Fattah al-Sisi condemned the attack and declared a three-day period of national mourning.

"Vicious terrorism is being waged against the country's Copts and Muslims. Egypt will emerge stronger and more united from this situation," al-Sisi said in a statement.

Sisi blamed the attack on a suicide bomber named Mahmoud Shafiq Mohammed Mustafa. He said that four people had been arrested and two more suspects are believed to be involved.

Coptic Christians comprise about 10 percent of the Egyptian population. Most Copts live in Egypt, but there are about a million members of the Church outside the country. St. Mark's Cathedral is considered as the Church's headquarters and the home of its leader, Pope Tawadros II.

Tawadros was visiting Greece when he learned about the attack, Reuters reported. He cut his visit short and issued a statement calling for unity.

"The whole situation needs us all to be disciplined as much as possible ... strong unity is the most important thing," he said in a speech aired on state television.

The church attack came after a bomb explosion killed six policemen on Saturday at a checkpoint on the main road leading to the pyramids of Giza. It was thought to be the deadliest attack on security forces in Cairo in more than six months. A newly formed militant group known as Hasm claimed responsibility for the attack on Saturday.

The Egyptian Christian community has long complained about discrimination from their Muslim neighbors. The last major attack on a church occurred on a New Year's service in Alexandria just weeks before the start of the 2011 uprising. It resulted in the deaths of at least 21 people.