Baghdad (IANS) -- The Iraqi State Board of Antiquities and Heritage has announced it was restoring monumental sculptures vandalised by militants of the extremist group Islamic State (IS) in the historic city of Hatra in northern Iraq.

In the middle of an Iraqi desert, nearly 90 km southwest of Nineveh's provincial capital Mosul, Hatra stands with its monumental sculptures and high walls full of inscriptions and watchtowers dating back to 2,000 years ago, Xinhua news agency reported.

At a ceremony held on Thursday at the archaeological site of Hatra, the State Board of Antiquities revealed some monumental sculptures that have been restored during the past three months by Iraqi experts in cooperation with Italy's International Association of Mediterranean and Oriental Studies, under the sponsorship of the International Alliance for the Protection of Heritage in Conflict Areas.

Ali Abi Shalgham, Representative of the Iraqi Minister of Culture, told Xinhua that 'many archaeological sites in Nineveh province were under maintenance, including the archaeological site of Hatra.'

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The first phase of restoration has completed in the Hatra ruin site, which included the rehabilitation of the administrative headquarters, the maintenance of some of the ancient city's walls, as well as the restoration of some statues and pieces on the arches of temples, according to Shalgham.

Massimo Vidale, Scientific Director of the Italian expedition, told Xinhua that restoring the vandalised antiquities that decorated the buildings and reflected the grandeur of the city is an essential part of their work.

'We restored many destroyed artifacts and at the same time built some buildings, and we have also collected thousands of pieces of artifacts and will return them to their original locations,' said Vidale.

After Saddam Hussein's regime was toppled by troops led by the US in 2003, about 15,000 pieces of cultural relics from the Stone Age, the Babylonian, Assyrian, and Islamic periods were stolen or destroyed by looters, according to official statistics.

The Mosul Museum and the ancient cities of Hatra and Nimrud were destroyed and large numbers of antiquities were smuggled after the IS militants took control of large territories in northern and western Iraq in 2014.

More than 10,000 sites in Iraq are officially recognised as archaeological sites, but most of them are not properly protected and many are still being looted.