A twin suicide bombing killed more than 60 people at a church service in northwest Pakistan on Sunday, officials said, in what is believed to be the country’s deadliest attack on Christians.

The two attackers struck at the end of a service at All Saints Church in Peshawar, the main town in Khyber Pakhtunkhwa province which has borne the brunt of a bloody Islamist insurgency in recent years.

Doctor Mohammad Iqbal of Peshawar’s Lady Reading Hospital told AFP that 61 people had been killed and 120 wounded. Fellow doctor Sher Ali confirmed the numbers.

Sahibzada Anees, one of Peshawar’s most senior officials, told reporters the bombers struck when the service had just ended.

“Most of the wounded are in critical condition,” Anees said.

“We are in an area which is a target of terrorism and within that area there was a special security arrangement for the church. We are in a rescue phase and once it is over we will investigate what went wrong.”

Former minister for inter-faith harmony Paul Bhatti and provincial lawmaker Fredrich Azeem Ghauri both said the attack was the deadliest ever, targeting Christians in Pakistan.

The small and largely impoverished Christian community suffers discrimination in overwhelmingly Muslim-majority Pakistan but bombings against them are extremely rare.

Schoolteacher Nazir Khan, 50, said the service had just ended and at least 400 worshippers were greeting each other when there was a huge explosion.

“A huge blast threw me on the floor and as soon as I regained my senses, a second blast took place and I saw wounded people everywhere,” Khan told AFP.

An AFP reporter saw shreds of human flesh and bloodstains on the walls and floor of the church, whose windows had been ripped apart by the blast.

Pages of a Bible were scattered near the altar and rice meals mingled with dust on the floor amid shattered benches. Walls were gouged with ball bearings used in the explosives, he said.

Grieving relatives blocked the main Grand Trunk Road highway with bodies of the victims to protest against the killings, an AFP reporter said.

Christians in Karachi, Lahore, Multan and other cities also staged protest rallies to condemn the killings and demand state protection for their lives and properties, AFP reporters said.

In the southern port city of Karachi angry protesters clashed with police when they tried to clear a road in Isa Nagri, a low-income Christian neighbourhood.

Pakistan’s Ulema Council, an association of leading Muslim scholars, strongly condemned the church attack and said killing innocent people violates the tenets of Islam.

“It is an extremely shameful attack which has shamed all Pakistanis and Muslims,” Allama Tahir Mehmood Ashrafi, chief of the council, told AFP.

“There is no room for such terrorist acts in Islam.”

Sectarian violence between majority Sunni and minority Shiite Muslims is on the rise in Pakistan. Sunday’s attack will fuel fears the already beleaguered Christian community could be increasingly targeted.

Islamist militants have carried out hundreds of bombings targeting security forces and minority Muslim groups they regard as heretical, but attacks on Christians have previously largely been confined to grenade attacks and occasional riots.

Khyber Pakhtunkhwa is a deeply conservative province bordering the tribal districts along the Afghan frontier which are home to Taliban and Al Qaeda militants.

Provincial lawmaker Ghauri said there were about 200,000 Christians in the province, of whom 70,000 lived in Peshawar.

“Now after this attack Christians across Pakistan will fear for their lives,” Ghauri warned.

Pakistan Prime Minister Nawaz Sharif strongly condemned the bombings.

“Terrorists have no religion and targeting innocent people is against the teachings of Islam and all religions,” Sharif said in a statement.

Sharif said such “cruel acts of terrorism reflect the brutality and inhumane mindset of the terrorists.”

Only around two percent of Pakistan’s population of 180 million are Christian. The community complains of growing discrimination.

The US Commission on International Religious Freedom has warned that the risk to Pakistan’s minorities has reached crisis levels.

Christians have a precarious existence in Pakistan, often living in slum-like “colonies” cheek-by-jowl with Muslims and fearful of allegations of blasphemy, a sensitive subject that can provoke outbursts of public violence.

In the town of Gojra in Punjab province in 2009, a mob burned 77 houses and killed seven people after rumours that a copy of the Islamic holy book the Koran had been desecrated during a Christian marriage ceremony.

Rimsha Masih, a Christian girl who was arrested for alleged blasphemy last year, fled to Canada with her family in June after the charges were dropped.