The Chinese government "systematically dismantled" CIA spying operations in China starting in late 2010, according to The New York Times.
The paper reports that the Chinese government killed at least a dozen CIA sources and imprisoned up to eight others over the next two years. One was shot in front of his colleagues in the courtyard of a government building, according to the report.
The newspaper cites 10 current and former U.S. officials, who describe the intelligence breach as one of the worst in decades. They spoke on condition of anonymity.
The report published Saturday says U.S. intelligence and law enforcement agencies scrambled to stem the damage, but were bitterly divided over the cause of the breach.
According to the report, debates between U.S. officials were punctuated with "macabre" phone calls - "We lost another one" - and urgent questions from the Obama administration for answers.