PESHAWAR, Pakistan — A suicide bomb attack on a historic church in northwestern Pakistan killed at least 71 people Sunday, officials said, the deadliest-ever assault on the country's Christian minority.

The bombing in Peshawar, which wounded another 110 people, underlines the threat posed by Islamic extremists as the government seeks a peace deal with domestic Taliban militants. It will likely intensify criticism from those who believe that negotiating peace with militants is a mistake.

Two suicide bombers attacked during a Christian church service, detonating explosives inside the church while as many as 600 people listened to a sermon, Zaheer ul Islam, Peshawar’s deputy commissioner, told state-run Pakistan TV. The death toll reached 71 people with 110 injured, Shaukat Yousafzai, health minister for Khyber Pakhtunkhwa province, told reporters in comments broadcast on Dunya TV.

"There were blasts and there was hell for all of us," said Nazir John, who was at the church. "When I got my senses back, I found nothing but smoke, dust, blood and screaming people. I saw severed body parts and blood all around."

Survivors wailed and hugged each other in the wake of the blasts. The white walls of the All Saints Church were pockmarked with holes likely caused by ball bearings or other metal objects contained in the bombs to cause maximum damage. Blood stained the floor and was splashed on the walls. Plates filled with rice were scattered across the ground.

The number of casualties from the blasts was so high that the hospital was running out of caskets for the dead and beds for the wounded, said Mian Iftikhar Hussain, a former information minister of surrounding Khyber Pakhtunkhwa province who was on the scene.

"What have we done wrong to these people?" asked one of the wounded, John Tariq, referring to the attackers. "Why are we being killed?"

Tariq's father was killed by the blasts, he said.

No one has claimed responsibility for the attack, but suspicion will likely fall on one of the country's many Islamic militant groups. Islamic militants have been blamed for previous attacks on the Muslim country's Christian minority, as well as Muslim groups they consider heretics.

"This is the deadliest attack against Christians in our country," said Irfan Jamil, the bishop of the eastern city of Lahore.

The bishop in Peshawar, Sarfarz Hemphray, announced a three-day mourning period and blamed the government and security agencies for failing to protect the country's Christians.

"If the government shows will, it can control this terrorism," said Hemphray. "We have been asking authorities to enhance security, but they haven't paid any heed."

Islamic militants have carried out dozens of attacks across the country since Pakistani Prime Minister Nawaz Sharif took office in June, even though he has made clear that he believes a peace deal with the largest group, the Taliban, is the best way to tamp down violence in the country.

Pakistan's major political parties endorsed Sharif's call for negotiations earlier this month. But the Taliban have said the government must release militant prisoners and begin pulling troops out of the northwest tribal region that serves as their sanctuary before they will begin talks.

Sharif condemned the church attack in a statement sent to reporters, saying, "the terrorists have no religion and targeting innocent people is against the teachings of Islam and all religions."

"Such cruel acts of terrorism reflect the brutality and inhumane mindset of the terrorists," he said.