UNITED NATIONS — Members of a deeply divided United Nations Security Council spent two hours on Tuesday morning looking at pictures of mutilated, skeletal corpses that were said to have been taken by a former Syrian Army photographer.

Some victims, who were allegedly detained by the Syrian government, had been starved for weeks, which explained why ribs poked out and abdomens looked like sunken valleys, a forensic pathologist told the Council. One person appeared to have been strangled by a metal belt from an automobile engine. The ankles of several were scarred; the pathologist said they had probably been shackled and starved, so that the skin had lost all strength.

These and more photographs were shown to the Council in an effort by France to refer Syria to the International Criminal Court. They were part of a collection smuggled out of Syria by a defector known by the code name Caesar. An international panel of experts hired by Qatar, one of the Syrian government’s staunchest critics, found the photographs to be authentic and Caesar to be credible. Aside from the pathologist, Dr. Stuart J. Hamilton, the panel included a forensic imaging expert and three war crimes prosecutors.

New details on Tuesday emerged about Caesar and his photographs. His job was to chronicle the deaths of detainees during the Syrian conflict. For two years, he took pictures of the dead as his job demanded. He also made copies of each photograph, smuggling them to a member of the opposition. His own death was faked so that he could escape the country.