Story highlights ISIS fighters seized the ancient city of Palmyra in Syria last month

Palmyra residents reported two Muslim shrines' destruction to Syrian authorities

(CNN) ISIS fighters have destroyed two ancient Muslim shrines in the oasis city of Palmyra, the Syrian government confirmed Wednesday, the latest act of cultural vandalism by the Sunni extremists.

ISIS seized control of Palmyra , a UNESCO World Heritage Site dating back 2,000 years, last month, prompting fears for the site's survival.

An email sent on behalf of Syria's antiquities chief, Maamoun Abdulkarim, head of the Directorate-General of Antiquities and Museums, said the body had heard four days ago from people in Palmyra of the shrines' destruction.

"ISIS has blown up two ancient Muslim shrines in Palmyra, and has published photos of this awful crime against the Syrian cultural heritage on Facebook," the statement said.

Photos: Historic sites damaged by ISIS Photos: Historic sites damaged by ISIS ISIS seized control of Palmyra , a UNESCO World Heritage Site dating back 2,000 years, in May, prompting fears for the site's survival. The Syrian government confirmed ISIS fighters have destroyed two Muslim shrines in the ancient oasis city. It's the latest act of cultural vandalism by the Sunni extremists. Hide Caption 1 of 12 Photos: Historic sites damaged by ISIS ISIS released a propaganda video showing its fighters destroying Iraq's ancient Assyrian city of Nimrud in March. The destruction follows other attacks on antiquity carried out by the militant group in Iraq and Syria. The United Nations has described such deliberate cultural destruction as a "war crime." Hide Caption 2 of 12 Photos: Historic sites damaged by ISIS The Iraqi Ministry of Tourism and Antiquities announced in March that ISIS had bulldozed the ruins of Nimrud, seen here in 2009. Hide Caption 3 of 12 Photos: Historic sites damaged by ISIS Bas-relief panels from the Palace of Ashurnasirpal II are seen in Nimrud in 2009. Hide Caption 4 of 12 Photos: Historic sites damaged by ISIS This file photo from 2003 shows the ancient ruins of Hatra in Iraq. It is another one of the cultural sites that have reportedly been damaged by ISIS. Hide Caption 5 of 12 Photos: Historic sites damaged by ISIS Bas-reliefs of masks in Hatra Hide Caption 6 of 12 Photos: Historic sites damaged by ISIS A statue of the goddess Shamiya, or Shahiro, at Hatra in 2009 Hide Caption 7 of 12 Photos: Historic sites damaged by ISIS In this image made from video posted on a social media account affiliated with ISIS, a militant uses a power tool to destroy a winged-bull Assyrian protective deity at the Nineveh Museum in Mosul, Iraq. Hide Caption 8 of 12 Photos: Historic sites damaged by ISIS "It's tragic to see this destruction," said William Webber, from the UK-based Art Loss Register. "Each time you see this you think it can't happen again, but it does." The Mosul museum held 173 original pieces of antiquity and was being readied for reopening when ISIS invaded Mosul in June. Hide Caption 9 of 12 Photos: Historic sites damaged by ISIS An exterior shot of Nineveh in May 2008 Hide Caption 10 of 12 Photos: Historic sites damaged by ISIS Two Parthian Kings of Hatra, seen in the Mosul museum in 2008 Hide Caption 11 of 12 Photos: Historic sites damaged by ISIS In July, a video was released showing the destruction of Jonah's Tomb in Mosul. The tomb was inside a Sunni mosque, seen here in 2008, called the Mosque of the Prophet Yunes (Arabic for Jonah). Hide Caption 12 of 12

One of the tombs destroyed is that of Mohammed bin Ali, a descendent of Ali bin Abi Taleb, the Prophet Mohammed's cousin, the website DGAM said. It's in a hilly area 4 kilometers (2.5 miles) north of Palmyra.