ONCUPINAR BORDER CROSSING, Turkey -- On Saturday afternoon, a Syrian man who gave his name as Sobhi was standing on the side of the road a few feet inside of Turkey, with his mother and father and all of his worldly belongings.
During three years of warfare and siege, Sobhi, who is 26 and works as a tailor, had steadfastly refused to leave his hometown of Aleppo, despite persistent shortages of fuel and food -- and the government's tactic of dropping imprecise explosive barrels on civilian areas.
But over the past week, he said, the bombings from these deadly barrels -- often little more than steel cylinders packed with explosives and metal scraps -- have grown so intense that he could no longer stay in the city. Hundreds have been killed in the attacks since the beginning of the year, observers say.
"The situation is terrible," Sobhi said. "The bombs are falling constantly, there's no electricity, no water, trash is piling up on the streets."
Officials and monitoring groups say the exodus from Aleppo in recent days has been unprecedented. They estimate that hundreds of thousands of residents of the rebel-held side of the city have fled in the direction of Turkey and the northern countryside. Aleppo lies less than 50 miles south of the Turkish border.
Another 100,000 or more have fled across front lines -- and past a feared bridge often targeted by snipers -- to reach the regime-controlled side of the city, according to official estimates. Before the war, Aleppo was Syria's largest city, with a population estimated around 2.5 million.
In a statement earlier in the week, U.S. Secretary of State John Kerry called the barrel bombings "the latest barbaric act of a regime that has committed organized, wholesale torture, used chemical weapons, and is starving whole communities by blocking delivery of food to Syrian civilians in urgent need."
He was joined on Friday by United Nations Secretary General Ban Ki-Moon, who condemned the attacks through his spokesman.
Just about everyone who can leave the rebel neighborhoods -- those whose movement is not limited by money or sickness -- has departed, or is trying to, Sobhi said.
"It's an entirely empty city -- a city of ghosts," he said. "If you went there, you would be scared to even cross the street."
Sobhi was wearing a brown leather bomber jacket and thin framed glasses, and he had a steely expression on his face. A crowd had gathered around him as he spoke, clamoring to share their tales of misery, or frustrations with Turkish border officials, who have only let Syrians into the country in intermittent dribbles. Tens of thousands more Syrians are said to be awaiting processing on the other side of the border.
"We left some people back there and feel terrible about it," Sobhi said of Aleppo. "How are they going to live?"
"Those who are going to die are going to die," a man standing behind Sobhi responded solemnly. "What can they do?