Batnaya, North Iraq -- Churches still lie in ruin six years after the Islamic State (ISIS) swept through the Nineveh Plains, with others slowly rebuilt by Christians returning to the remains of their villages.

The St Qaryaqous Chaldean Church in Batnaya, 20 kilometers north of Mosul, has not been rebuilt due to a lack of aid.

Najib Batrs' grandfather built the church in 1944.

"At least 70 percent is destroyed. We can't rebuild it. It is still in ruins. We ask for someone to rebuild it, be it the international NGOs or the central government," he said.

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ISIS destroyed more than 30 churches in Mosul and 40 across the Nineveh Plains.

Most Christians fled to the Kurdistan Region as the terror group advanced.

St George's Chaldean Church, in Tilsqof, was renovated in 2017.

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"When ISIS arrived, most churches were either destroyed or burned, or ISIS left insulting graffiti on the walls. When we returned, we started slowly rebuilding them. We rebuilt the sacred sites so they are ready for worship, as a house of God," said priest Karam Najib.

1.5 million Christians lived in Iraq before 2003. Only 350,000 remain, according to figures provided by Chaldean bishop Najib Mikhael and MP Klara Odisho Yaqub.