Media reports say militants from the Islamic State (IS) terrorist group have destroyed part of the Roman amphitheater in the ancient city of Palmyra.

The militants destroyed the facade of the second-century theater along with the Tetrapylon, a cubic-shaped ancient Roman monument that sits in the middle of the colonnade road that leads to the theater, The Associated Press (AP) cited Maamoun Abdulkarim, the head of Syria's antiquities department, as saying.

Abdulkarim told The Associated Press that reports of the destruction first trickled out of the IS-held town late in December. But satellite images of the damage were only available late Thursday, confirming the destruction.

The imagery, provided by the US-based American Schools of Oriental Research (ASOR), show significant damage to the Tetrapylon and the theater.  The ASOR said the damage is likely caused by intentional destruction from IS but they were unable to verify the exact cause, according to The Associated Press.

Abdulkarim said only two of the 16 columns of the Tetrapylon remain standing. The stage backdrop has sustained damage, according to ASOR.

Syrian state-run news agency SANA reported the damage Friday. 

The jihadists recaptured the UNESCO-listed archaeological site in December from government troops.  IS previously held the site for ten months up to March 2016.

The group is known to have destroyed other monuments before it was forced out by a Russian-backed government offensive.

BBC reports IS militants on January 19 beheaded four people and shot eight others dead, outside a museum close to the archaeological site.

The militants have previously carried out killings in the Roman amphitheater.

Palmyra is also a strategic crossroads linking the Syrian capital, Damascus, with the country's east and neighboring Iraq.  Located 215 kilometers east of Damascus, the city was once home to 65,000 people before the Syrian civil war began.  However, most Palmyra residents did not return after it was retaken by the government.  Activists estimated the city is now home to a few hundred families; many of them tried to flee as IS recaptured the city in December, according to The Associated Press.