Syrian Arab Army forces flattened the Eliyahu Hanabi Synagogue in the Jobar neighborhood of Damascus over the weekend. The attack not only wrecked a site that’s at least 400 years old. It may have destroyed thousands of irreplaceable Jewish artifacts contained inside the synagogue, according to opposition leaders and photos obtained at the site.

The area where the synagogue once stood has been under bombardment by the forces of Syrian President Bashar al-Assad for months. The Syrian regime is laying siege to the town, one of the few rebel strongholds in the area. It’s all part of what the opposition calls Assad’s “scorched earth” policy, which includes random and violent attacks on civilian populations.

“I am deeply saddened to learn of the destruction of Jobar Synagogue, which was a treasure of Jewish and Syrian cultural heritage,” said Shlomo Bolts, an official at the Syrian American Council, an American charity connected to the Syrian opposition.