With their hold on territories in Iraq quickly slipping away, desperate fighters from the Islamic State (ISIS) terrorist group are making last-ditch efforts to leave a path of destruction.

According to a report from The Sun, ISIS militants fleeing back towards Mosul have deliberately desecrated churches and decimated Christian villages in the nearby city of Qaraqosh, the oldest and what used to be the largest Christian area in the Middle Eastern nation.

The website posted photos of The Immaculate Conception Church at the city centre, which was left in ruins by the ISIS. The church's bell tower was partially destroyed, the windows appeared black and blown up, while the cross on the dome was purposely taken down.

Worse, a statue of Jesus Christ inside the church was shown to have been beheaded by the ISIS militants. Walls of the place of worship were also vandalised and were ridden with bullets.

Saleh Abu-Yousef, a 32-year-old Christian fighter, also told The Sun how the ISIS fighters used the church's central square to train for warfare.

"They used the courtyard as target practice...they even cut the head off of our beloved statue of Jesus," Saleh lamented.

Aside from churches, the extremist group also destroyed commercial areas in Qaraqosh, and also rendered a local school almost unusable.

"You can see ISIS hand of destruction everywhere," said the Christian fighter, who was forced to take up arms to be able to defeat the terrorist in his homeland.

Still, Saleh is optimistic that his city will rise from the ashes. He shared how the city was able to hold its first Holy Mass following its liberation from the ISIS militants, describing it as a "good day."

Likewise, Christian faithful like him are slowly returning to Qaraqosh and trying to rebuild their homes and their lives.

"It was the first time Christians had returned to our church in over two years," he said.