An injured woman receives medical treatment at a hospital in northwest Pakistan's Peshawar on Sept. 22, 2013.[Photo/Xinhua]

ISLAMABAD - At least 56 people were killed and 120 others injured when a twin suicide bomb attack hit a Christian church in Pakistan's northwest city of Peshawar on Sunday, hospital sources said.

Chief executive of Lady Reading Hospital in Peshawar, which admitted all the blast victims, told local media that they have received 56 dead bodies including two policemen, 10 women and 15 children, and over 120 injured.

He said that the death toll may further rise as over 20 among the injured were in critical condition.

Briefing about the attack, Zaheer-ul-Islam, deputy commissioner of Peshawar, said that the incident happened at about 11:45 a.m. local time when two suicide bombers blew up their explosive-laden vests inside the church when around 500 to 600 people of Christian community were coming out of the church after offering Sunday prayers.

He confirmed that the blast hit the Christian church called " Pakistan Church" in Kohati Gate area of Peshawar, killing about 60 people and wounding over 100 others wounded.

Shafqat Malik, inspector general of Bomb Disposal Squad, said that the blasts took place one after another and the two suicide bombers were carrying an estimated seven kg of explosives each in their explosive vests.

He said that they found a head of one of the suicide bombers from the roof of the church, which is being examined by the medical team.

Priest Ijaz, administrator of the church, said that the blasts occurred when some people were going back to their homes after prayers and some were having lunch outside the prayer hall.

Talking to media, father of a deceased minor girl said "We were going out of the church after expressing our gratitude to God in prayers when the bomber attacked us, he killed our women, our kids and our men mercilessly."

The bomb attack triggered off a protest by the Christian community in the city.      

Christian community across the country announced a three-day protest against the incident and urged the government to provide security to churches across the country.

Bishop Sadiq Daniel, representative of Christian community in Pakistan, condemned the attack and said that no religion allows anyone to attack religious places.

Security at all churches across the county was beefed up following the blast, said local media.

No group has claimed responsibility for the attack yet.

Both Pakistani President Mamnoon Hussain and Prime Minister Nawaz Sharif have condemned the attack.