Dr. David Nott said the snipers are playing a "targeting game" that includes noticeably pregnant women and young children, CNN reported Wednesday.
"Most of the children removed were 7, 8, 9 months gestation, which meant it was fairly obvious to anybody that these women were pregnant," Nott said.
Photos provided to CNN by Syria Relief, the aid agency through which Nott volunteers, show a young girl, estimated to be about 5 years old, lying in a hospital bed with head wounds. Another girl, thought to be the same age, had a gaping wound to her forehead.
Nott told CNN 90 percent of surgeries he performed on any given day were for sniper wounds.
On some days, the wounds were similar.
"After a while we noticed that there were certain trends going on," Nott said. "We had some days, say, 10 or 15 gunshot wounds of which eight or nine of them were targeted in one particular area. So for example, one day, we received say 15, 16 gunshot wounds and of that eight to nine were targeted in the left groin only."
"Then the following day they were targeted in the right groin only," he said. "So it seemed to me like there was some of thing going on -- a game going on -- between the snipers."
Nott said local doctors he worked with told him they had learned snipers were receiving presents -- such as cigarettes -- for people they'd shot during the day.
In video from Aleppo obtained by CNN, men, women and children try to avoid sniper bullets as they cross from the regime-controlled area to rebel-held areas for food and provisions.
Nott said the situation reminded him of Bosnia in the 1990s, CNN said. However, the United Nations operated humanitarian corridors then to ensure aid got through despite the fighting.
Syria, he said, needs the same set-up.
"Now is the time to develop a humanitarian corridor to allow health and aid workers to go in, and not feel threatened on the way in and not feel threatened on the way out," he said.
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