Khaled Asaad was a respected scholar who devoted more than five decades of his life to preserving the majestic, 2,000-year-old ruins of Palmyra, a city in the Syrian desert.

On Tuesday, Islamic State extremists beheaded the former chief of antiquities in the city and left his body hanging in public for terrified residents to view, according to the official Syrian Arab News Agency (SANA).

The killing of Asaad, confirmed by Syrian activists, marks not just another attack by the Islamist militants on the region’s vast archeological heritage but also an assault on those who look after it. The 82-year-old archeologist was killed after he refused to divulge information on “specific archeological treasures,” according to SANA, which cited comments from the government’s antiquities chief, Maamoun Abdulkarim.

Abdulkarim told the news agency that the militants crucified Asaad “on colonnades in central Palmyra.”

However, a photograph posted on Twitter purports to show Asaad’s body hanging from a street lamppost. A sign on the corpse described the killing as punishment for working with “idols,” an apparent reference to the area’s Roman-era artifacts.

Palmyra seized by the Islamic State

The Islamic State captured Palmyra in May, prompting fears that the group would destroy the UNESCO World Heritage site, about 150 miles northeast of the capital, Damascus. Syrian activists say the group has killed hundreds of residents in the city, which had a pre-civil war population of about 200,000.

Last month, the Islamic State, also known as ISIS or ISIL, released a video showing child soldiers summarily executing 25 government troops in the city’s Roman amphitheater. In the video, the boys are shown firing pistols into the heads of the soldiers, who are kneeling with their hands tied behind their backs.

In addition to perpetrating mass murder, the Islamic State has carried out sweeping anti-idolatry campaigns, laying waste to vast amounts of precious artifacts in the areas of Syria and Iraq under its control. The group uses extremist interpretations of Sunni Islam to justify the destruction, which often targets pre-Islamic artifacts and other symbols of multiculturalism viewed as idolatrous.

In March, the group used bulldozers and explosives to level Nimrud, an ancient Assyrian city in Iraq. A video released in February purports to show the group’s members wielding sledgehammers against statues in the museum of Mosul, the largest city in northern Iraq.

In June, the militants blew up two ancient shrines in Palmyra that were not part of its Roman-era ruins. No evidence has emerged that the rest of the heritage site has been ransacked. The group has channeled its violence in the area mostly toward people, such as Asaad, considered a pioneer in Syrian archeological circles.

Among other accomplishments, he authored volumes of scholarly works on Palmyra, and he teamed up with Western archaeological missions to excavate and research the city’s ancient tombs and temples.

The last moments of Asaad’s life were spent in his beloved Palmyra, in a public square where he was killed, according to the Britain-based Syrian Observatory for Human Rights, which monitors the civil war.

Kaplan reported from Washington.

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