At least 75 people were killed by two bomb explosions at the All Saint's Church in Peshawar's Kohati Gate area on Sunday.
Apart from the dead, 130 others were injured in the incident.
The victims included children and women.
The injured are reportedly being treated at the Lady Reading Hospital.
Pakistani media quoted Additional Inspector General Shafqat Malik of the Bomb Disposal Squad, as saying that two suicide bombers had carried out the attack.
He said some of the body parts of the attackers had been recovered and sent for forensic examination.
About six kilograms of explosives were used in the attack, he added.
The first attack happened when services had finished and people were leaving the church. The second blast was carried out inside the church, the Dawn quoted an official, as saying.
The two attackers also opened fire on security guards deployed at the church, killing one and injuring the other before entering the church.
The bombs were detonated within an interval of 30 seconds.
Tension prevails in the area, and all markets and shops have closed down.
Enraged protestors took to the streets and set ablaze the belongings of police personnel deployed at the church for security.
The All Saints Church resembles a mosque and has served as a symbol for peace and harmony.
Peshawar's Kohati Gate area is one of the sensitive localities. It has at least three churches and several mosques.
