(CNN) ISIS fighters have destroyed part of the historic Roman amphitheater in the ancient city of Palmyra.
The amphitheater in the ancient oasis city of Palmyra, Syria, before it was captured by ISIS.
Syrian authorities say recent satellite images confirm renewed devastation in the ancient oasis city, according to a statement Friday from the Syrian Directorate General for Antiquities and Museums.
"The imagery shows significant damage to the Tetrapylon and the Roman Theater, caused [as a] result of intentional destructions by ISIS," the statement said.
It wasn't immediately clear exactly when the damage occurred, but officials say the new satellite photograph showing damage was taken on January 10, 2017.
The jihadist group first seized control of Palmyra, a UNESCO World Heritage Site, in May 2015. Syrian regime forces managed to briefly push the militants out of the city last year.
But Palmyra fell to ISIS again in December when Syrian troops pulled out and over 4,000 militants returned.
How ISIS ravaged Palmyra's world treasures
Before: The ruins of the 2,000-year-old Temple of Baalshamin are seen in Palmyra, Syria, in 2007. The ISIS militant group took over the ancient city last year and razed parts of its
World Heritage Site. Syrian government forces recaptured the ancient city from the terror group in March 2016. Click through to see the landmarks before and after ISIS' occupation.
After: A Syrian government soldier walks near what's left of the Temple of Baalshamin on Sunday, March 27. Syrian forces retook the city days before, but damage had already been done by ISIS. UNESCO says it plans to evaluate the extent of
Palmyra's damage soon. Many of the structures -- which date from the first and second centuries and marry Greco-Roman techniques with local traditions and Persian influences -- remain in place, bolstering hopes that ISIS didn't completely raze the world heritage site.
Before: The Arch of Triumph in 2006.
After: The Arch of Triumph on March 27.
Before: The Temple of Bel in 2008.
After: The Temple of Bel on March 27.
Destroyed statues are seen inside the damaged Palmyra Museum on March 27.
Many statues in the museum had their faces chipped off -- in keeping with strict Sharia interpretations of the depiction of human forms.
Before ISIS invaded, authorities took what they could from the museum. But larger items and those fixed to walls had to be left behind.
Destroyed statues inside the Palmyra Museum.
The Syrian directorate-general of antiquities and monuments was positive that the condition of artifacts meant that they could be restored and their "historic value" returned, according to a translation of an article on the
department's website.
ISIS took over Palmyra in May.
By June, ISIS began destroying historical sites.
Damage inside the Palmyra Museum.
Palmyra was a caravan oasis when Romans overtook it in the mid-first century. In the centuries that followed, the area "stood at the crossroads of several civilizations" with its art and architecture mixing Greek, Roman and Persian influences, according to UNESCO.
Omar Albenia, a spokesman of the council of Palmyra and Badia condemned the vandalism, while castigating the Syrian regime for allowing jihadists to reclaim the city.
"This is a great loss for the people of Palmyra and what Palmyra stands for in history, because it is an important historical site that was well preserved over the years," he told CNN.
"We at the council of Palmyra and Badia condemn this cowardly terrorist attack carried out by ISIS and also place the blame of the Syrian regime of what is happening in Palmyra when the city of Palmyra has exchanged hands between ISIS and the Syrian regime several times."
Albenia added that the council had been surprised at the Syrian regime's decision to leave Palmyra when it was not secure. He questioned why Syrian government troops have been able to recapture Aleppo but not do the same in the comparatively smaller city of Palmyra.
Syrian state news also reported that 12 civilians were executed by ISIS militants in Palmyra on Thursday.
CNN's Fred Pleitgen contributed to this report.