Soon after the start of the protests, we began receiving messages from an underground network of doctors and nurses in the country — most sent through encrypted messaging apps to evade the regime’s surveillance apparatus. Medical professionals described hospital floors slick with blood, teenagers with severe pellet and gunshot wounds, and bodies rushed in from nearby streets. The crackdown extended to medical staff members. Physicians and nurses who treated protesters were threatened for providing care, and dozens of them have been detained. Many are still being held without charges. Amid the chaos, some medical workers quietly began preserving evidence of the massacre and its aftermath — X-rays, scans, photographs and patient records that they say contradict official accounts of the unrest. Providing care became an act of courage and defiance.