A former CIA officer was arrested at a New York airport after authorities found two highly classified notebooks that contained information on undercover US spies, the Department of Justice said on Tuesday, report agencies.
Jerry Chun Shing Lee, 53, a naturalized US citizen who now lives in Hong Kong, was detained at JFK airport and charged with unlawful retention of national defence information on Monday.
The case is thought to be linked to an FBI investigation, which began in 2012, into the crippling of the CIA's spy operation in China.
In August 2012, FBI agents searched Lee's hotel rooms during a trip to Virginia via Hawaii. Inside his luggage, they found two small handwritten notebooks containing the real names, contact details and meeting locations of covert CIA agents, according to an affidavit by Kellie R. O'Brien, that was filed to the district court in Eastern Virginia.
Sources close to the case have said that Lee leaked the information to China and as a result, around 20 undercover US agents have been killed or captured, NBC news reported.
"Agents found two small books containing handwritten notes that contained classified information, including but not limited to, true names and phone numbers of assets and covert CIA employees, operational notes from asset meetings, operational meeting locations and locations of covert facilities," DOJ confirmed.
Officials have not explained why it took over five years to arrest Lee, however he was interviewed on five separate occasions around May and June 2013. During those interviews, the former agent never acknowledged the existence of the notebooks or offered to hand them over to U.S. officials, according to O'Brien.
"As a case officer, Lee was trained in methods of covert communications, surveillance detection, recruitment of assets, handling of assets, payment of assets, operational security, and documenting, handling and securing classified material," O'Brien wrote in the affidavit.
In 2010, China began to destroy US spy operations by slowly capturing and killing over a dozen sources within two years.
