In pictures: Karachi Christian attack

Unidentified gunmen have attacked a Christian charity in Pakistan's port city of Karachi, killing seven people after tying them up and gagging them.

The attack on the Institute for Peace and Justice is the latest to target Pakistan's minority Christian community.

Family and friends of the victims gathered soon after the attack

Police were alerted by the sole survivor who was spared by the attackers

One of two men wounded in the attack later died in hospital

It was the fifth attack on Christians and foreigners since Pakistan joined the US-led war on terror

Security had been tightened after the arrest of militants with maps of Christian targets