BEIRUT (AP) -- Islamic State group militants destroyed the landmark ancient Tetrapylon and parts of the 2nd century Roman theater in Syria's historic town of Palmyra, the government and opposition monitoring groups said Friday.
Maamoun Abdulkarim, the head of Syria's antiquities department, said 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.
Satellite imagery obtained by the Boston-based American Schools of Oriental Research show extensive damage to the Tetrapylon. DigitalGlobe satellite imagery also shows damage to the theater facade.
IS militants recaptured the ancient town in December from government troops - nine months after they were expelled in a Russia-backed offensive. During their first stay, IS destroyed ancient temples including the Temple of Bel, which dated back to A.D. 32, and the Temple of Baalshamin, a structure of stone blocks several stories high fronted by six towering columns. The group also used the theater for public killings and shared a chilling video of it.
The militants also blew up the Arch of Triumph built between A.D. 193 and A.D. 211.
Abdulkarim told The Associated Press he fears for what remains of the city's ancient relics.
"When Palmyra fell for the second time, we shed tears because we expected this terror," Abdulkarim said. "Now we are destined to see more terror if (IS control of Palmyra) continues."
Abdulkarim said reports of the destruction first trickled out of the IS-held town late in December. But satellite images of the damage only became available late Thursday, confirming the destruction.
The ASOR said the damage was likely caused by intentional destruction from IS but the organization was unable to verify the exact cause.
Abdulkarim said only two of the 16 columns of the Tetrapylon remain standing. The Palmyra Tetrapylon, characterized by its four plinths that are not connected overhead, had only one original ancient column, said Abdulkarim. The 15 other columns were modelled after the ancient one and installed by Palmyra's 81-year old distinguished antiquities scholar Khaled al-Asaad, who was killed by IS militants when they were in the town the last time. They hung his body from a Roman column.
It was not immediately clear if the original column survived the destruction, Abdulkarim said.
ASOR said new stone debris was scattered across the center stage from damage to the stage backdrop that is also the facade of the theater.
The extremists have destroyed ancient sites across their self-styled Islamic caliphate in Syria and Iraq, viewing them as monuments to idolatry.
State-run news agency SANA reported the damage Friday and Syrian opposition monitors also confirmed but gave no immediate details.
A UNESCO world heritage site, Palmyra boasts 2,000-year-old towering Roman-era colonnades and priceless artifacts. Syrians affectionately refer to it as the "Bride of the Desert."
A desert oasis surrounded by palm trees in central Syria, Palmyra is also a strategic crossroads linking the Syrian capital, Damascus, with the country's east and neighboring Iraq. Located 155 miles (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 residents tried to flee as IS recaptured the city in December.
On Thursday, reports emerged that the militant group killed 12 captives it held in Palmyra, some of them beheaded in the Roman theater.