Dozens of hidden Syriac manuscripts were recovered by Iraqi security forces late on Tuesday following the arrest of a suspected ISIS member in the northern Nineveh governorate.
The manuscripts were stolen from Assyrian churches in Mosul after the city became the extremist group's de facto capital in the country between 2014 and 2017.
An international military coalition led a battle for nine months that ousted the insurgents from the city in late 2017.
“The arrest of a suspected ISIS member led to the recovery of 32 archaeological books that were in his possession. The man hid the books in his kitchen,” Mosul police chief, Laith Al Hamdani said in a statement.
The books were found in Bab Al Jadid district in the old city of Mosul, Mr Al Hamdani said.
For nearly three years ISIS controlled large parts of Iraq and Syria, claiming that it was creating a caliphate.
The battle to drive them out destroyed large parts of the city, which killed thousands of civilians and displaced more than 900,000 others.
Iraqi Christians suffered immensely under their rule with the majority of the population fleeing the city after the militants threatened to kill them unless they converted to Islam or paid a “protection tax”.
The country is home to one of the world’s most ancient Christian communities but its population had decreased following the sectarian violence that began in 2003 after the US-led invasion.
Iraq hosted nearly 1.5 million Christians prior to the invasion but shortly before the rule of ISIS over 800,000 had immigrated abroad to the US and Europe, according to a report by the Atlantic Council.
The Christians that were left in Mosul fled to the semi-autonomous Kurdish region in the north after ISIS, but while victory over the insurgents provided a window of opportunity for them to return, very few had done so.
This is partly to do with the grim state of Iraqi politics as it faces one of its biggest challenges in reigning in armed militias that control the territory formerly occupied by ISIS.