TAIPEI (Taiwan News) – China’s Taiwan Affairs Office (TAO) admitted on Wednesday (Sept. 25) it has detained a Taiwanese man who went missing in China in 2018.

TAO spokesperson Ma Xiaoguang (馬曉光) confirmed at a regular press briefing that Taiwan national Tsai Chin-shu (蔡金樹) was arrested in July 2018. He said the charge was “endangering China’s national security” and confirmed Tsai was being held in custody.

He rebutted media reports about Tsai being “unaccounted for,” saying his family had been notified. Furthermore, he claimed Tsai’s legal rights would be respected, wrote Liberty Times.

Taiwanese scholar Chiang Min-chin (江岷欽) alleged in a talk show aired on Sept. 12 that Tsai had been detained in China for national security reasons, reported Central News Agency. Taiwan’s Straits Exchange Foundation corroborated the next day that the organization was notified by Tsai’s family in August last year that he had gone missing after visiting Quanzhou, in Fujian Province, for a food product event.

Tsai, 60, is an expert in cross-strait relations and leads an organization in southern Taiwan that promotes exchanges between Taiwan and China. Chiang stressed that Tsai is a staunch member of the so-called blue camp, regarded as pro-China, said LTN.

Since President Tsai Ing-wen (蔡英文) assumed office in May 2016, the Straits Exchange Foundation has received 149 reports of missing Taiwan nationals in China. The whereabouts of 67 remain a mystery, wrote CNA.