A Taiwan military court sentenced an intelligence officer to life in prison Thursday after convicting him of spying for China.
Maj. Chuang Po-hsin was found guilty of passing to China information his military division had gathered about the mainland's military activities.
Chuang, an electronic surveillance officer, was one of 17 officers and civilians arrested in May and charged with passing secrets to China.
Defense officials said he did not have access to highly confidential information, but passing it to China would give the mainland insight into Taiwan's intelligence operations.
The spy ring was reportedly discovered by accident as part of an investigation into credit card fraud.
Taiwan and mainland China both run intelligence networks in each other's territory, with occasional arrests and convictions of alleged spies on both sides, the BBC reports.