Egyptian President, Abdel-Fattah al-Sisi, said that, a Cairo church blast that killed 25 people on Sunday, was carried out by a suicide bomber.

Speaking to mourners during the funeral of those killed, Sisi said that a 22-year-old man called Mahmoud Shafiq, blew himself up inside Saint Peter and Saint Paul Church in Cairo’s Abassiya neighbourhood.

So far, no group has claimed responsibility for the attack that also left 49 others injured.

However, the bombing came one day after a top Egyptian court confirmed a death sentence against leading militant extremist, Adel Habbara, over an anti-military attack that killed at least 25 soldiers in restive North Sinai province in 2013.

Sisi also revealed that four people, including a woman, in connection with the attack have been arrested, adding that, security forces are searching for two more suspects.

“We will revenge for this church blast…the attack is a sign of terrorists’ frustration,” Sisi said.

In 2013, angry Islamist protesters attacked a number of churches and homes of Coptic Christians, across the North African country, for their support to the military’s removal of Islamist president, Mohamed Morsi.

Although there are no accurate statistics, some reports said that Coptic Christians constitute over 10 percent of the 92 million population of the most populous Arab state.

In Egypt, bomb attacks are endemic in North Sinai Province, where the ABM group has carried out hundreds of anti-security attacks, following the ouster of Morsi by the army, in response to mass protests against his rule in 2013.

Some attacks crept to Cairo and other major cities across the most populous Arab country.-