Gunmen on a motorcycle killed a Christian priest and wounded another as the victims drove home from church in Peshawar in Pakistan's northwest, police said on Sunday.
William Siraj, 75, was killed instantly in the attack on the city's ring road, according to police, while his colleague reportedly received hospital treatment for non life-threatening injuries. A third cleric in the car was unharmed.
Police said they were studying CCTV footage in their search for the attackers.
Religious minorities under threat
The clerics were said to be from the Church of Pakistan, a union of Protestant churches including the Methodists and the Anglicans.
The most senior bishop in the Church of Pakistan, Azad Marshall, condemned the attack and tweeted: "We demand justice and protection of Christians from the Government of Pakistan."
No one has immediately claimed responsibility for the shooting. But militant attacks on security forces have been on the rise in Pakistan's northwestern areas which border Afghanistan.
Many of them have been claimed by Tehrik-e-Taliban Pakistan, a group that associates itself with the Afghan Taliban. The group ended a one-month cease-fire with the government in December, with militant violence on the rise in recent weeks.
Peshawar was the scene of a twin suicide bombing outside a church in 2013 that killed scores of people in what was one of the deadliest attacks on Christians in Pakistan. A memorial service for Siraj is to be held in the same church, All Saint's Church, on Monday.
Christians and other non-Muslims often face intimidation and persecution in Pakistan, with attacks sometimes also targeting members of minority Muslim faiths such as Ahmaddiyas and Shiites.