Islamist militants in Iraq and Syria continue their war on the region’s cultural heritage, attacking archaeological sites with bulldozers and explosives.

The so-called Islamic State (ISIS) released a video that shocked the world last month by showing the fiery destruction of the Temple of Baalshamin, one of the best-preserved ruins at the Syrian site of Palmyra. Last weekend, explosions were reported at another Palmyra temple, dedicated to the ancient god Baal; a United Nation agency says satellite images show that larger temple has largely been destroyed.

The destruction is part of a propaganda campaign that includes videos of militants rampaging through Iraq's Mosul Museum with pickaxes and sledgehammers, and the dynamiting of centuries-old Christian and Muslim shrines.

ISIS controls large stretches of Syria, along with northern and western Iraq. There's little to stop its militants from plundering and destroying sites under their control in a region known as the cradle of civilization.

The militant group is just one of many factions fighting for control of Syria, where a civil war has left more than 230,000 dead and millions more homeless.

The group claims the destruction of ancient sites is religiously motivated; Its militants have targeted well-known ancient sites along with more modern graves and shrines belonging to other Muslim sects, citing idol worship to justify their actions. At the same time, ISIS has used looting as a moneymaking venture to finance military operations.

“It’s both propagandistic and sincere,” says Columbia University historian Christopher Jones, who has chronicled the damage on his blog. “They see themselves as recapitulating the early history of Islam.”

A guide to cultural sites that ISIS has damaged or destroyed so far:

Palmyra

Palmyra thrived for centuries in the desert east of Damascus as an oasis and stop for caravans on the Silk Road. Part of the Roman Empire, it was a thriving, wealthy metropolis. The city-state reached its peak in the late 3rd century, when it was ruled by Queen Zenobia and briefly rebelled against Rome.

Zenobia failed, and Palmyra was re-conquered and destroyed by Roman armies in A.D. 273. Its colonnaded avenues and impressive temples were preserved by the desert climate, and in the 20th century the city was one of Syria’s biggest tourist destinations.

ISIS seized the modern town of Palmyra and the ancient ruins nearby were seized in May. The militants initially promised to leave the site’s columns and temples untouched. Those promises were empty: In August, they publicly executed Khaled al-Asaad, a Syrian archaeologist who oversaw excavations at the site for decades, and hung his headless body from a column.

View Images The Temple of Baal Shamin at Palmyra was attacked last month by ISIS fighters using improvised explosives. The group released photos of the destruction, and satellite images have since confirmed the Roman-era building was wiped out. Photograph by Kyodo, AP

And the group released photos last month of militants rigging the 1,900-year-old Temple of Baalshamin with explosives and blowing it up. It was one of Palmyra’s best-preserved buildings, originally dedicated to a Phoenician storm god. Now it is nothing but rubble.

Just days later, explosions were reported at the Temple of Baal, a nearby structure that was one of the site’s largest, and a United Nations agency says the building was flattened.

Mar Elian Monastery

The Christian monastery was captured in August, when ISIS militants captured the Syrian town of al-Qaryatain near Palmyra. Dedicated to a 4th-century saint, it was an important pilgrimage site and sheltered hundreds of Syrian Christians. Bulldozers were reportedly used to topple its walls, and ISIS posted pictures of the destruction on Twitter.

Apamea

A rich Roman-era trading city, Apamea has been badly looted since the beginning of Syria's civil war, before ISIS appeared. Satellite imagery shows dozens of pits dug across the site; previously unknown Roman mosaics have reportedly been excavated and removed for sale. ISIS is said to take a cut from sales of ancient artifacts, making tens of millions of dollars to fund their operations.

Dura-Europos

A Greek settlement on the Euphrates not far from Syria's border with Iraq, Dura-Europos later became one of Rome's easternmost outposts. It housed the world's oldest known Christian church, a beautifully decorated synagogue, and many other temples and Roman-era buildings. Satellite imagery shows a cratered landscape inside the city's mud-brick walls, evidence of widespread destruction by looters.

Mari

Mari flourished in the Bronze Age, between 3000 and 1600 B.C. Archaeologists have discovered palaces, temples, and extensive archives written on clay tablets that shed light on the early days of civilization in the region. According to reports from locals and satellite imagery, the site, especially the royal palace, is being looted systematically.

View Images The Temple of Baal was one of the main attractions at Palmyra, a Roman-era trading outpost in the desert northeast of Damascus, Syria. A UN agency says it was mostly flattened over the weekend by explosions detonated by ISIS. Photograph by Sandra Auger, Reuters

Hatra

Built in the third century B.C., Hatra was the capital of an independent kingdom on the outskirts of the Roman Empire. Its combination of Greek- and Roman-influenced architecture and Eastern features testify to its prominence as a trading center on the Silk Road. Hatra was named a UNESCO World Heritage site in 1985.

In 2014, Hatra was taken over by ISIS and reportedly used as an ammo dump and training camp. A video released by ISIS in April 2015 showed fighters using sledgehammers and automatic weapons to destroy sculptures in several of the site’s largest buildings. "The destruction of Hatra marks a turning point in the appalling strategy of cultural cleansing underway in Iraq," UNESCO head Irina Bokova said at the time.

Nineveh

Ancient Assyria was one of the first true empires, expanding aggressively across the Middle East and controlling a vast stretch of the ancient world between 900 and 600 B.C. The Assyrian kings ruled their realm from a series of capitals in what is today northern Iraq. Nineveh was one of them, flourishing under the Assyrian emperor Sennacherib around 700 B.C. At one point, Nineveh was the largest city in the world.

View Images NG MAPS

SOURCE: INSTITUTE FOR THE STUDY OF WAR

Its location on the outskirts of Mosul—part of the modern city is built over Nineveh's ruins—put it in ISIS's crosshairs when the group took over the city in 2014. Many of the site's sculptures were housed in the Mosul Museum (see entry below), and some were damaged during the rampage through the museum documented on video. Men were also shown smashing half-human, half-animal guardian statues called lamassus on Nineveh's ancient Nirgal Gate. “I’m not sure there’s much left to destroy in Mosul,” says Columbia’s Jones.

Mosul Museum and Libraries

Reports of looting at Mosul's libraries and universities began to surface almost as soon as ISIS occupied the city last summer. Centuries-old manuscripts were stolen, and thousands of books disappeared into the shadowy international art market. Mosul University's library was burned in December. In late February, the ISIS campaign escalated: Mosul's central public library, a landmark built in 1921, was rigged with explosives and razed, together with thousands of manuscripts and instruments used by Arab scientists.

The book burning coincided with the release of the video showing ISIS fighters rampaging through the Mosul Museum, toppling statues and smashing others with hammers. The museum was Iraq's second largest, after the Iraq Museum in Baghdad. Statues included masterpieces from Hatra and Nineveh.

Margarete van Ess, head of the German Archaeological Institute's Iraq field office, says that a trained eye can tell that about half of the artifacts destroyed in the video are copies; many of the originals are in the Iraq Museum.

Nimrud

Nimrud was the first Assyrian capital, founded 3,200 years ago. Its rich decoration reflected the empire's power and wealth. The site was excavated beginning in the 1840s by British archaeologists, who sent dozens of its massive stone sculptures to museums around the world, including New York's Metropolitan Museum of Art and the British Museum in London. Many originals remained in Iraq.

View Images The walls of Nineveh were built around A.D. 700 to protected the Assyrian capital, at the time probably the largest city in the world. In February, ISIS fighters released video of fighters smashing sculptures and gates at the ancient site. Photograph by Randy Olson, Nat Geo Image Collection

The site itself is massive: An earthen wall surrounds 890 acres. The Iraqi Ministry of Tourism and Antiquities says ISIS bulldozed parts of the site, but the extent of the damage isn't yet clear. Some of the city was never uncovered and remains underground—protected, one hopes.

Khorsabad

Khorsabad is another ancient Assyrian capital, a few miles from Mosul. The palace there was built between 717 and 706 B.C. by Assyria's King Sargon II. Its reliefs and statues were remarkably well preserved, with traces of the original paint still decorating depictions of Assyrian victories and royal processions.

Most of the reliefs and many of the statues were removed during French excavations in the mid-1800s and by teams from Chicago's Oriental Institute in the 1920s and '30s, and are now in the Iraq Museum in Baghdad as well as in Chicago and the Louvre in Paris. It's not clear what part of the site ISIS targeted.

"We don't have photography showing how far the damage might go," van Ess says. "The only information right now is from local people and Iraqi antiquities ministry."

Mar Behnam Monastery

Established in the 4th century, the monastery was dedicated to an early Christian saint. The holy site, maintained since the late 1800s by Syriac Catholic monks, survived the Mongol hordes in the 1200s but fell to ISIS in March. The extremists used explosives to destroy the saint’s tomb and its elaborate carvings and decorations.

Mosque of the Prophet Yunus

Mosul's Mosque of the Prophet Yunus was dedicated to the biblical figure Jonah, considered a prophet by many Muslims. But ISIS adheres to an extreme interpretation of Islam that sees veneration of prophets like Jonah as forbidden. On July 24, ISIS fighters evacuated the mosque and demolished it with explosives.

Like many of Iraq's sites, the mosque was a layer cake of history, built on top of a Christian church that in turn had been built on one of the two mounds that made up the Assyrian city of Nineveh.

Imam Dur Mausoleum