The Islamic State has looted or destroyed a considerable portion of the Tal Ajaja archaeological site in northeastern Syria, according to Agence France-Presse. Khaled Ahmo, director of antiquities in Hasakah province, where the ancient mound is located, told AFP that “more than 40 percent of Tal Ajaja was destroyed or ravaged” by the extremist group’s fighters.

The militants had overrun the area in 2014, but in recent months they were chased out of whole stretches of Hasakah by a campaign led by Kurdish militias. In the wake of the Islamic State’s departure, the extent of the damage the militants have wrought is being steadily discovered.

Tal Ajaja, about 30 miles from the border with Iraq, is one of a series of vast Mesopotamian mounds rich in artifacts and relics going back about three or four millennia. In 2014, video emerged of Islamic State militants smashing Assyrian statues at the site. According to the extremist group’s apocalyptic creed, representations of deities and sites of pre-Islamic worship are worthy of destruction. As the group’s fighters wreaked havoc on the civilian populations caught up in their onslaught, they also pulverized what they could of the region’s supposedly apostate history.

Moreover, as my colleague Loveday Morris detailed last year, the Islamic State — also known as ISIS and ISIL — developed a lucrative, illicit trade in smuggling the antiquities it chose not to smash. This also was the case in Tal Ajaja, where the militants dug tunnels in previously untouched areas of the site and unearthed hitherto unknown treasures — most of which have disappeared.

“They found items that were still buried, statues, columns. We’ve lost many things,” Maamoun Abdulkarim, head of Syria’s antiquities department, told AFP.

He added: “These barbarians have burnt pages of Mesopotamia’s history. In two or three months, they wiped out what would have required 50 years of archaeological excavations.”

It’s one of the many bitter ironies of the moment that the Islamic State — an outfit driven by a puritanical zeal and a nihilistic penchant for violence — has taken root in one of the most archaeologically rich parts of the world. The stretches of northern Iraq and Syria where the group has seized territory are home to many layers of history and the ruins of dozens of ancient civilizations, including some of the world’s first urban societies.

The regime of Syrian President Bashar al-Assad has used the Islamic State’s razing of the past and ransacking of museums as part of its propaganda. After regime forces recaptured Palmyra, a UNESCO World Heritage site, with Russian support this year, the government held a concert in the site’s Roman-era amphitheater.

Russian President Vladimir Putin beamed in via video conference and declared the liberation of Palmyra from the Islamic State a “sign of hope in the battle against terrorism.”

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