Ukraine accused Russia of turning the Tauride Chersonese in Crimea, a UNESCO World Heritage site, into a “historical and archaeological park” and called on the United Nations to intervene.

The site, an ancient city founded by Greeks in the 5th century BC on the northern coast of the Black Sea, was added to the UNESCO World Heritage List in 2013. The following year, Russia illegally annexed the Crimean peninsula. Ukraine and its allies do not recognize Russian sovereignty over Crimea, a key access to the eastern Mediterranean, and have been fighting for its return since the occupation began.

The new complex, called New Chersonese, houses a Russian Orthodox monastery and several facilities, including a museum of Christianity and the Museum of Crimea and New Russia. (New Russia is the term Russia uses for the annexed territories in Crimea.) The complex was built by the Russian Defense Ministry with funding from the state-controlled Transneft corporation and is headed by a clergyman appointed by Russian President Vladimir Putin. It was officially opened on July 28.

On July 24, Dmytro Lubinets, the Ukrainian parliament’s human rights commissioner, appealed to the UN to protect the site, calling its redevelopment part of Russia’s plan to destroy Ukrainian heritage.

Russia has “completely destroyed the authentic monument of world importance, Tauride Chersonese,” Lubinets said in a statement on his Telegram channel. “They have started illegal construction work on the ruins and are actually building a new city, the so-called historical and archaeological park.”

In a new report, Evelina Kravchenko of the Institute of Archaeology of the National Academy of Sciences of Ukraine said Tauride Chersonese had been “disturbed.” In addition, “tens of thousands of finds” had been destroyed, Kravchenko said. “Some of them were picked up by locals from these dumps, both for personal storage and for sale on the black market. Therefore, we will soon be able to see things from Chersonesos on online auctions.”

The annexation has raised legal and ethical challenges for Ukraine and the international cultural sector. In November, the Allard Pierson Museum, a historical museum in Amsterdam, sparked controversy when it returned 400 artifacts, including valuable Sythian gold, to a Kyiv museum. The collection had been loaned to Amsterdam by four museums in Crimea before the annexation, and after the incident, both Ukraine and Crimea demanded the return of the artifacts.

“This was a special case in which cultural heritage fell victim to geopolitical developments,” said Els van der Plas, director of the Amsterdam museum, in a statement.

Since invading Ukraine, the Russian military has been repeatedly denounced by international monitoring groups for its blatant attacks on Ukrainian cultural heritage. In April, Ukraine’s Kherson Art Museum identified 100 paintings allegedly looted by Russian troops, according to a video shot at a museum in Crimea. The museum said the 100 artworks caught on camera likely represented “less than 1 percent” of the loot looted from Ukrainian museums.