UNESCO Director-General Irina Bokova
UNESCO Director-General Irina BokovaReuters

The head of the UN cultural organization, UNESCO, on Wednesday called for a campaign against the "culture cleansing" being carried out by Islamic State (ISIS) jihadists.

"Extremists don't destroy heritage as a collateral damage, they target it systematically to strike societies at their core," Irina Bokova said in a speech at the Chatham House think tank in London, according to the AFP news agency.

"This strategy seeks to destroy identities by eliminating heritage and cultural markers," she said.

Several archaeological sites have been attacked by ISIS jihadists in Iraq and Syria and  their recent takeover of an area including the ruins of the ancient city of Palmyra in Syria sparked worldwide concern.

In April, ISIS released a video in which its terrorists can be seen using rifles and sledgehammers to destroy artifacts at the ancient fortress city of Hatra, famed for its unique blend of eastern and western architecture.

UNESCO on Wednesday named 2,000-year-old Hatra as one of its 'Heritage in Danger' sites, joining the likes of the Everglades and the Old City of Jerusalem.

The site was listed due to the "destruction inflicted.. by armed groups," UNESCO said in a statement quoted by AFP.

Earlier, the jihadists also damaged the site of Iraq's ancient Assyrian city of Nimrud and destroyed dozens of pieces from the museum in Mosul.

"I think the growing awareness that hard power will not be enough to defeat violent extremism is gaining ground. We need also soft power," Bokova said on Wednesday.

"Culture should be part of our response to violent extremism," she added.

UNESCO is currently meeting in Bonn in Germany for its 39th committee session until July 8 and will consider at least 36 natural and cultural sites vying to get World Heritage status.

It was at the meeting in Germany that Hatra received its special classification.

The organization has launched a campaign called "United Heritage" to defend historical sites under threat from jihadists and to counter terrorist propaganda.

AFP contributed to this report.