Religious freedoms campaigners are concerned there could be a repeat of the suicide bomb attack at a church in the city of Quetta exactly one year ago. Nine people were killed.
Speaking to Premier from Pakistan, Mehwish Bhatti from the British Pakistani Christian Association (BCPA) said: "So many lost their lives just because they were attending a Christmas service.
"So many were injured and there were different casualties. It really makes a Christian feel very insecure in Pakistan."
A memorial service for the victims was held by the Bishop of Karachi Rt Revd Sadiq Daniel at Bethel Memorial Methodist Church - under the watch of security services.
The BPCA says it has been helping scores of families affected by the attack to meet funeral costs and medical fees. The youngest victim, an 18-month old girl, lost a leg in the incident.
Local church leader, pastor Adil said: "Those who lost family members wept but also rejoiced that those lost are now in heaven.
"We sang our carols exuberantly as we remembered Christ who came that we might all now have access to the kingdom heaven."
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