ISIS Kills, Mutilates 400 Women and Children after Capturing Ancient City of Palmyra

May 26, 2015 12:38 PM EDT

The Islamic State extremist group has executed at least 400 people, mostly women and children, and mutilated their bodies in the ancient city of Palmyra since it was captured last week, Syrian state television has revealed in a disturbing new report.

"The terrorists have killed more than 400 people ... and mutilated their bodies, under the pretext that they cooperated with the government and did not follow orders," The Independent quoted the state news agency on Sunday, adding that the majority of the victims are women and children.

The report reveals that the hundreds of those killed were from groups and families loyal to the government, which is currently engaged in a civil war both against ISIS and other rebel groups. The group is also said to be holding some 600 detainees, whom they have accused of a variety of crimes, including apostasy and "dealing with the regime forces, and hiding regime's members in their homes."

Last week, Islamic State forces entered the ruins located in the city of Palmyra after taking complete control over the area on Thursday, forcing Syrian government forces to retreat. The group, which is bent on expanding its brutal caliphate, now controls more than half of Syrian territory, including the central city's military air base, prison and intelligence headquarters

CNN notes that city of Palmyra itself could become one of ISIS' next casualties, as the group is known for destroying priceless historic artifacts. Palmyra is a UNESCO World Heritage site, largely for its well preserved Roman era ruins which unite Greek, Roman and Persian influences.

British historian and novelist Tom Holland noted that the destruction of Palmyra would be a "severe loss" and "tragedy" for the entire world.

"Mesopotamia, Iraq, Syria, this is the wellspring of global civilization," he told CNN. "It really couldn't be higher stakes in terms of conservation."

In March, the group bulldozed the ancient Assyrian city of Nimrud in northern Iraq and looted priceless items dating back 13 centuries B.C., including statues and other historic objects.

Earlier, the group released a video showing them destroying Assyrian era statues and sculptures in Mosul, formerly home to thousands of Christians. In addition to leveling a fourth-century Syrian monastery, the group is faulted with destroying a tomb believed to be that of biblical prophet Jonah.

While the jihadist group has justified the destruction by claiming the religious statues, manuscripts and relics are "idolatrous," experts believe the militants traffic the items to fund their military and destroy only those pieces that are too large to be smuggled.

"They have networks that allow them to traffic in cultural treasures," said Fawaz Gerges, professor of Middle East studies at The London School of Economics. "They have made tens of millions of dollars selling artworks."

Meanwhile, there have been mounting questions over Obama's strategy in the war against ISIS in the wake of the capture of Palmyra and the key Iraqi city of Ramadi.

Following Ramadi's recent fall, Sen. John McCain, R-Ariz., who is the chairman of the Senate Armed Services Committee, called the strategy employed in the region "one of the most disgraceful episodes in American history."

House Speaker John Boehner, R-Ohio, also reportedly told the president that his request for military authorization to continue the fight against terror needs to be revised as it is ineffective in its current state.

"The president's plan isn't working," he said, ABC reported. "It's time for him to come up with a real, overarching strategy to defeat the ongoing terrorist threat."