Two famous ancient structures in the city of Palmyra have been destroyed by ISIS forces, Syria’s antiquities chief says.

The Tetrapylon and the facade of the city’s Roman theater have both been almost completely demolished, the official says, according to NPR’s Alison Meuse.

“Activist Khaled al-Homsi, who is from Palmyra, shared satellite imagery to Twitter, which appears to confirm the scale of the damage,” Alison reports. “The face of the Roman theater is a pile of rubble and only four of the Tetrapylon’s 16 columns appear to be standing.”

More: ISIS Destroys Ancient Theater, Tetrapylon In Palmyra, Syria Says : The Two-Way : NPR