Following its seizure of the Syrian city of Palmyra, the Islamic State (IS) now controls more than 50 percent of Syrian territory, according to the UK-based Syrian Observatory for Human Rights (SOHR).
This gain comes days after IS captured the city of Ramadi, which is the provincial capital of Anbar, Iraq's largest province. Ramadi provides IS with control over an important strategic highway that links Iraq and Syria; the capture of Ramadi and Palmyra in one week signals significant momentum for the militant fundamentalist group.
Palmyra is an oasis city, while the 2,000-year-old ruins adjacent to the city are a UNESCO World Heritage Site and perceived as a symbol of Syria's rich heritage and culture. The fear that the sites may be decimated is real: IS sees pre-Islamic antiquities and artifacts as idolatrous, while at the same time recognizing their value in selling them off to fund their activities.
SOHR released a statement on Thursday noting that — along with the fact that IS now controls a larger territory than Syrian president Bashar al-Assad — the group currently has power over the vast majority of the country's gas and oil fields.
At least 462 people had been killed during the IS attack on al- Sikhni and Tadmur between May 13 and May 20, said SOHR, including 71 executions during this period.
Though IS appears to control more than half of Syria's territory, a lot of that area is difficult terrain that is sparsely inhabited. Protecting Syria's main cities in the west have been a priority for the Syrian military and the Assad regime. But, noted the Wall Street Journal, capturing Palmyra offers a base for IS militants to advance on cities such as Homs and Damascus.
After a weeklong siege, IS seized Palmyra on Wednesday, and later released a statement claiming they had gained full control over the city's airport and the notorious Tadmur Prison — infamous for the torture and abuse that has historically occurred inside.
Charlie Winter, a researcher for the London-based anti-extremism think tank the Quilliam Foundation told VICE News that while the percentage of territory held is shocking, "clearly in terms of the actual population it doesn't control anywhere near as much as 50 percent — I think that's very important to note. In terms of the economy it doesn't control anywhere near as much as 50 percent. And while it is a very striking number it's not necessarily indicative of the fact that the Islamic State is the most powerful actor in Syria at the moment."
Winter also suggested that the latest offenses might be deliberately timed to "maintain the idea that it is a dominant group that is acting as an expansive Sunni vanguard."
With the first anniversary of the declaration of the caliphate coming up, Winter said, "In no way can [IS] look like it's in a weaker position than it was this time last year."
Related: Looting and Destruction Feared as Islamic State Seizes Syria's Ancient City of Palmyra
Mourning the loss of Palmyra, Syrian antiquities chief Maamoun Abdulkarim told Reuters, "This is the fall of a civilization. Human, civilized society has lost the battle against barbarism. I have lost all hope."
This was me, overcome with awe, in Palmyra 22 years ago. How many people will ever get to see it now? — Daniel Hannan (@DanHannanMEP)May 20, 2015
Related: The Islamic State (Full Length)
UNESCO Director General Irina Bokova said she was "extremely worried" about the capture of Palmyra and the destruction that could ensue. "Any destruction of Palmyra is not just a war crime, but will mean an enormous loss for humanity," she said. "We need a total mobilization of the international community," who she said needed to join together in launching an appeal to stop the destruction.
Related: Islamic State's Capture of Ramadi May Signal Larger Role For Iraq's Militias as Conflict Continues
Follow Sally Hayden on Twitter: @sallyhayd