TAIPEI (Taiwan News) – The Straits Exchange Foundation (SEF) has asked China for information about a 22-year-old man who disappeared after arriving in Shanghai last month, reports said Friday (Sept. 20).

Relatives of Kuo Yu-hsuan (郭宇軒) said he had notified them of his safe arrival in the Chinese city on Aug. 27, but nothing had been heard from him since. Kuo planned to travel onward to Hefei in the province of Anhui, per CNA.

All attempts to contact him failed, leading his relatives to post notices online and to report him as missing. A sister said they feared he had been forced into work by a fraud ring, or had been abducted.

SEF has notified its Chinese counterpart, the Association for Relations Across the Taiwan Straits (ARATS), about Kuo’s case, but has not received a reply.

After a picture was released of the missing man wearing a school uniform, Chung Shan Industrial and Commercial School in Kaohsiung confirmed Kuo was a former student. He graduated about four years ago, per UDN.

Kuo’s disappearance followed the failure of a Formosa Plastics Group executive to return home from China. The Mainland Affairs Council has previously warned Taiwanese visitors to be careful about their actions and words during trips to China.

In June, the Chinese authorities published “22 Guidelines” threatening action, including the death penalty, against what they called active supporters of Taiwan independence. Taiwan condemned the threats as vague, harsh, and arbitrary, endangering everyone who China might want to take action against.