The Egyptian Interior Ministry announced on Wednesday that four more people have been arrested in connection with the bombing at St Mark's Cathedral in Cairo last December.
The bombing initially killed at least 25 people who were mostly women and children, Reuters reported. The Health Ministry revealed on Wednesday that the death toll had risen to 28.
One of the two main suspects were arrested along with three other men who were part of the same cell that is planning to carry out more attacks. Improvised explosive devices, shotguns and ammunitions have been found and seized by the police.
The Interior Ministry said that the police are still searching for another suspect named Mohab Mostafa el-Sayed Qassem, also known as "The Doctor." Qassem has been previously identified by the ministry as the group's leader, according to France 24.
The Egyptian government had initially linked the bombing to the Muslim Brotherhood, but ISIS claimed responsibility for the attack and identified the suicide bomber by his pseudonym, Abu Abdallah al-Masri.
The Brotherhood denounced the attack and accused the administration of President Abdel Fattah al-Sisi of failing to protect the church. Sisi, who took power in 2013 after deposing Mohamed Mursi of the Brotherhood, dismissed the accusation.
Meanwhile, the Coptic church that was damaged by the bombing has been fully repaired and restored by the Egyptian Armed Forces, according to Coptic news site Watani. Sisi wanted the church to be ready before Jan. 7, but it was finished a week ahead of schedule.
The damaged chandeliers, as well as the pews and the drapes, have been replaced. The wooden roof, the walls, doors and windows have been repaired, but the marks on the marble columns and stone walls were left in testimony and remembrance of the victims.
A team of Italian restorers will work on restoring the icons which go back to the outset of the 20th century.
Pope Tawadros presided over the Holy Mass at dawn on Jan. 1, and he joined the families of the victims for breakfast at the hall in the church afterward.