Then more reports of kidnappings started surfacing. By the end of March, as the government claimed to have retaken control of nearby cities, ransom demands were a daily occurrence in Aleppo, said Amal Hanano, a Syrian writer and analyst living in the United States. Usually, she said, the kidnappers asked for around $75,000 and then dropped their price to a fifth of that after tough negotiations.

Hur, using a nickname out of fear that he could be targeted again, said that his brother talked his kidnappers down to about $30,000 in Syrian pounds. It took a week. He said he spent most of the time tied to a water pipe in the back of a small store somewhere outside Aleppo.

His kidnappers made sure he had enough food and water. They took his cellphone, his watch and a gold ring but they left his car near the city, to establish their credibility. “They told my family where to find the car and the keys to prove that I was with them,” said Hur, indicating that they had probably kidnapped before.

In addition to gaining more expertise as the conflict drags on, criminals are also becoming more brazen. Yasmin said that a few days ago her cousin, a 65-year-old man, was robbed in his garden at 1:30 in the afternoon. His family watched helplessly as the thieves stole all he had, about $70. Now her brother, who lives across the street, makes sure his pockets are empty before he leaves home.

“We’ve all become a lot more careful since that incident,” Yasmin said. “Can you imagine? It’s not even safe to carry $70.”

Many Syrians blame the government of President Bashar al-Assad for allowing the crime to happen, or even encouraging it. Ms. Hanano, along with many activists, say the crime waves afflicting Syrian cities began over the past year when the unrest led to a guerrilla war. The battles themselves led to mass flight and empty streets, making it easier to crack open a store like a piñata.

It was Iraq, circa 2003, in miniature: in areas where decades of suppressive government have suddenly been lifted, looting, violence and sectarianism have begun to thrive.