In a social media post on Wednesday, the Ministry of State Security said the former assistant engineer at an unspecified research institute, surnamed Liu, had illegally copied and sold a large amount of classified information to an overseas espionage agency.
The ministry said Liu was unhappy about his perceived unfair treatment at work and that he had secretly copied classified documents before resigning from the research institute.
It said Liu had later sold the sensitive information to a foreign intelligence agency because he had financial problems stemming from failed investments.
The former engineer later attempted to sell information to other intelligence agencies in several countries before he was arrested and subsequently sentenced to death, according to the ministry. It did not say when the verdict was handed down.
