The blast took place at 12 noon (0700GMT), when people were attending Sunday services at a church in Quetta, the capital of the southwestern Balochistan province, local Geo News reported.
Sarfaraz Bugti, home minister for Baluchistan province, says hundreds of worshippers were attending services at the church ahead of Christmas. He says one attacker was killed at the entrance to the church while the other set off his payload inside. Police officer Mohammad Atiq confirmed the toll.
Rehmat Baloch, Balochistan's health minister, told reporters that four injured had been brought to the hospital.
Sarfraz Bugti, Balochistan's home minister, told Geo News that, according to initial reports, two militants stormed the church, and one blew himself up at the entrance, while the other was shot dead by security forces.
"A rescue operation is underway as our first priority is to save the lives of several people trapped in the church," he added.
A female eyewitness told reporters that the blast occurred when people were in services. The attack comes as Pakistan's tiny Christian community is preparing to celebrate Christmas.
Footage on local Geo News showed security forces rescuing women and children as shots being fired could be heard.
Local television showed ambulances and security patrols racing to the scene while women and children were being led out of the church's main gate.
In a statement, Prime Minister Shahid Khaqan Abbasi strongly condemned the attack, decrying how terrorists always target innocents.
"Terrorists have no religion, we will not allow them to disturb our peace and values, and they will be dealt with by the full might of the state," Abbasi said in a statement issued by his office.
The premier also expressed deep grief and sorrow over the loss of lives in the attack.
Sarfaraz Bugti, Balochistan's interior minister, praised the police and other security personnel for their prompt and timely action in rescuing hundreds of people trapped inside the church.
"God forbid, if the terrorists had succeeded in their plans, more than 400 precious lives would have been endangered," Bugti wrote on Twitter.
In September 2013, in Peshawar, northwest Pakistan, a twin suicide bomb attack at All Saints Church killed some 127 people and injured over 250, in the deadliest attack on Pakistan's Christian community in the nation's history.
8 killed, 44 wounded in suicide attack on Pakistan church
17 December 2017
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At least eight people have been killed and 44 are injured in a blast at a church in southwestern Pakistan, followed by security forces trying to overpower heavily armed militants, officials and local media reported.
