Site of Cairo church attack
Site of Cairo church attackReuters

The Islamic State (ISIS) jihadist group on Tuesday claimed responsibility for Sunday’s bomb attack on a Cairo Coptic church that killed 25 people, AFP reported.

The group claimed the attack in a statement circulated on social media, identifying the suicide bomber who carried out Sunday's attack by the pseudonym Abu Abdallah al-Masri.

The bomber "got in between the crowd" and detonated his explosive belt, the jihadist group said in the statement quoted by AFP.

ISIS warned it would continue attacks against "every infidel and apostate in Egypt, and everywhere".

Egyptian President Abdel Fattah al-Sisi named the suicide bomber as Mahmoud Shafik Mohamed Mostafa, 22, during a funeral for the victims on Monday.

Sisi said Mostafa had detonated his explosive belt at the Saint Peter and Saint Paul Church.

The interior ministry said late on Monday that Mostafa had been identified by DNA tests from body parts which matched that of his family.

The authorities have arrested four suspects, including a woman, Sisi said on Monday.

While Sisi did not name the organization the attackers were believed to belong to, state news agency MENA reported on Monday that the bomber and the suspects were all from areas of Egypt typically associated with strong support for the Muslim Brotherhood.

Coptic Christians, who make up about 10 percent of Egypt's population, have been previously targeted by jihadists.

In 2015, the Islamic State (ISIS) group released a video purportedly showing the beheading of the Coptic Christians it had captured in the Libyan capital Tripoli.