An explosion inside Cairo's Coptic cathedral killed at least 25 people and wounded 35, Egypt's state television said, in the second deadly attack to hit the Egyptian capital in two days.
Egypt's official MENA news agency said an assailant lobbed a bomb into a chapel close to the outer wall of St Mark's Cathedral, seat of Egypt's Orthodox Christian church and home to the office of its spiritual leader, Pope Tawadros II.
The attack took place as Egyptian Copts and other Christian denominations prepare to celebrate Christmas between December 25 and January 7.
Security forces estimate that the explosion was the result of a very large device left at the premises by a male or female suicide bomber, or that it was remotely activated while worshipers entered the Sunday service. It remains unclear how the device made it into the church, as the whole compound is secured and people entering it undergo a check.
Large contingents of security forces arrived at the scene following the blast, and roads leading to the cathedral were shuttered.
"I found bodies, many of them women, lying on the pews. It was a horrible scene," said cathedral worker Attiya Mahrous, who rushed to the chapel after he heard the blast. His clothes and hands were stained with blood and his hair matted with dust.
"I saw a headless woman being carried away," Mariam Shenouda said as she pounded her chest in grief. "Everyone was in a state of shock. We were scooping up people's flesh off the floor," she said.
"There were children. What have they done to deserve this? I wish I had died with them instead of seeing these scenes," she added.
There was no immediate claim of responsibility for the attack, but according to preliminary estimates, it was carried out by Islamic State's branch in Egypt.
Prime Minister Benjamin Netanyahu issued a condemnation of the Cairo attack. "Israel condemns the criminal terror attack in the Coptic Cathedral in Cairo. Israel sends its condolences to the families of the victims and the Egyptian people. We must join forces and fight terrorism together."
On Friday, two roadside bombs – one in Cairo and one north of the capital – killed six policemen and wounded six others.
Egyptian security forces are fighting an Islamist insurgency led by Islamic State's branch in North Sinai, where hundreds of soldiers and police have been killed. The insurgents have also launched deadly attacks Cairo and other cities.
On January 1, 2011, a similar attack took place in the Coptic cathedral of the seaside town of Alexandria. The blast occurred during a New Year service, killing and wounding dozens. The incident intensified the anger directed at the regime of then-President Hosni Mubarak, and was a harbinger of the events known as the January 25 Revolution that then led to the toppling of the president and his administration.
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