Two Egyptian churches have been attacked by bombs as worshippers celebrated Palm Sunday.
At least 37 people have died, and hundreds more have been injured.
At 10am, during the Easter service, the first bomb went off at St George's Coptic Church in Tanta, north of Cairo. Twenty-six people were killed and more than 50 others were injured.
A few hours later, St Mark's Coptic Church in the coastal city of Alexandria was targeted. Eleven people died and 66 were injured, according to the Egyptian Health Ministry.
The Tanta bombing was condemned as a terrorist attack by Egyptian authorities.
Ahmed Abu Zeid, spokesperson for Egypt's Ministry of Foreign Affairs, Tweeted: "Terrorism hits Egypt again, this time on Palm Sunday.
"Another obnoxious but failed attempt against all Egyptians."
Pope Francis spoke out about the attacks. He said that he had 'deep condolences to my brother, Pope Tawadros II, the Coptic church and all of the dear Egyptian nation'.
He added: "We pray for the victims of the attack carried out today, this morning, in Cairo, in a Coptic church."
He asked God 'to convert the hearts of those who spread terror, violence and death, and also the hearts of those who make and traffic in weapons'.
Egyptian state media reported that Coptic Pope Tawadros II was inside the church when the explosion struck, after leading worshippers in Palm Sunday prayers. It is unknown whether he was injured.
An eye witness told Reuters: "There was a huge explosion in the hall. Fire and smoke filled the room and the injuries were extremely severe.
"I saw the intestines of those injured and legs severed entirely from their bodies."
ISIS has claimed responsibility for the attacks.
Source: The Guardian, Daily Mail, New York Times, Radio Vatican, Reuters and The Mirror