December 2016: 25 people died when a bomb exploded at the Coptic cathedral in Cairo during a service. IS said it was behind the attack
February 2016: A court sentenced three Christian teenagers to five years in prison for insulting Islam. They had appeared in a video, apparently mocking Muslim prayers, but claimed they had been mocking IS following a number of beheadings
April 2013: Two people were killed outside St Mark’s cathedral in Cairo when people mourning the death of four Coptic Christians killed in religious violence clashed with local residents
The blasts came weeks before an expected visit by Pope Francis intended to show support for the country’s Christians, who make up about 10% of Egypt’s population and have long complained of being vulnerable and marginalised.
This sense of precariousness has only increased in recent years, with the rise of violent jihadism in parts of Egypt, the BBC’s Arab affairs editor Sebastian Usher says.
The community’s trust in the state’s ability and willingness to protect them will now be even more deeply shaken after the attacks, our correspondent adds.
The move by Mr Sisi is likely to raise concerns among human rights activists, observers say. The president, a former army chief, has been criticised by local and international groups for severe restrictions on civil and political rights in Egypt.
Human Rights Watch says tens of thousands of people have been arrested in a crackdown on dissent, and that security forces have committed flagrant abuses, including torture, enforced disappearances and likely extrajudicial executions.
What is the Coptic Christian faith?
The Coptic Orthodox Church is the main Christian Church in Egypt. While most Copts live in Egypt, the Church has about a million members outside the country.
Copts believe that their Church dates back to around 50 AD, when the Apostle Mark is said to have visited Egypt. Mark is regarded as the first Pope of Alexandria – the head of their church.
This makes it one of the earliest Christian groups outside the Holy Land.
The Church separated from other Christian denominations at the Council of Chalcedon (451 AD) in a dispute over the human and divine nature of Jesus Christ.
The early Church suffered persecution under the Roman Empire, and there were intermittent persecutions after Egypt became a Muslim country. Many believe that continues to this day.