DAMASCUS, Syria (AP) — Just as Leen Arbid entered the front gate of the Damascus Opera House, a potent symbol of the Assad family’s decades-long authoritarian rule over Syria, she heard a deafening bang. And then, everything went black.

The drama student was going to her classes that bright Sunday morning when a mortar shell fired from rebel positions on the outskirts of the Syrian capital struck the pavement inside the complex yard, next to an entrance door used by performers.