The breach was considered particularly damaging, with the number of assets lost rivaling those in the Soviet Union and Russia who perished after information was passed to Moscow by spies Aldrich Ames and Robert Hanssen, the report said.
Ames was active as a spy in the 1980s and Hanssen from 1979 to 2001.
A report by a prominent French newspaper has alleged China of spying on the African Union headquarters.
The Chinese-funded building in Addis Ababa is currently hosting the 30th summit of the pan-African body.
“She’s been spying on Rupert for years, giving money back to Chinese intelligence,” he said.