(CNN) A former CIA officer who is believed to have helped China identify and kill members of the US spy network in the country pleaded not guilty Friday in a Virginia federal court on charges of conspiracy to commit espionage and unlawful retention of classified information.

Judge T. S. Ellis III set a trial date for Jerry Chun Shing Lee for February 12, 2019.

Lee appeared unshackled in a green jumpsuit and glasses at the arraignment.

The Justice Department alleges that Lee, a former CIA case officer and US citizen, was asked to trade information for money by two Chinese intelligence officers in 2010 and 2011 while he lived in Hong Kong.

The former CIA officer is believed to have helped China dismantle a US spy network in the country and identify informants who were later killed or imprisoned. The New York Times reported in January that the imprisonment or execution of a dozen Chinese nationals working for the US was "one of the most devastating intelligence setbacks for the agency in recent decades."