What led to the capture of the ex-soldier accused of leaking military secrets to a foreign espionage agency?

The 80-year-old ex-soldier, who was skilled at counter-surveillance, was captured after Chinese national security officers intercepted communications from a foreign espionage agency instructing him to steal secrets from a specific military base. Despite his secretive nature and the challenging terrain where he was located, officers set a trap that led to his arrest. The Ministry of State Security discovered he had been sharing photos and videos of troop deployments, weapon configurations, and military barracks through social media accounts. The suspect had previously been dismissed from military service due to disciplinary issues.