Iraq's Christian minority took another hit Sunday evening when gunmen shot and killed an elderly Christian couple in their home.

The shooting took place in Baladiyat, a predominantly Shiite area in eastern Baghdad, and was the latest in a series of attacks that has left dozens of Christians dead in recent weeks.

Violence perpetrated by Islamic extremists has forced hundreds of thousands of Iraqi Christians to flee the country. Since 2003, the Christian population has shrunk from 1.2 million to 600,000, by some estimates.

The deadliest attack against the minority took place just recently on October 31, when suicide attackers stormed Our Lady of Salvation Church in Baghdad, killing 58 people and wounding 75.

The Islamic State of Iraq, an umbrella group for Sunni Islamic insurgent groups that include al-Qaida, has claimed responsibility for the attack at the Catholic church.

Remembering the victims of the October 31 attack, Cardinal Leonardo Sandri, prefect of the Congregation for Eastern Churches, reminded worshippers that nothing can destroy a religion that is based on the mystery of the cross.

"The church in fact does not diminish with persecution, rather it develops, and the Lord's field is enhanced by a more abundant harvest, when the grains of wheat which have fallen one by one, are reborn and multiply," he said last month during mass in St Peter's Basilica in Rome, which was attended by some of the survivors of the October attack.

Catholic bishops in the United States have called on members of Congress to pass a resolution condemning the violence and improving security for religious minorities in Iraq. The resolution was introduced last month by Rep. Chris Smith.