Officials in Taiwan demanded on Friday that Beijing disclose information about the disappearance of a Taiwanese man who had reportedly distributed photos of mainland Chinese troops massing equipment just outside protest-racked Hong Kong. Friends and family have been unable to reach Lee Meng-chu, a volunteer activity organiser with a small township in southern Taiwan, for 10 days, the Taiwanese government’s Mainland Affairs Council said after receiving pleas for help from Lee’s family members. “He was able to be contacted while in Hong Kong and then unreachable once he entered mainland China,” council spokesman Chiu Chui-cheng said. “The main thing now is we need to understand his movements and whereabouts, then eventually how to get him safely back to Taiwan.” Lee entered Hong Kong on August 18, Taiwan’s government-run Central News Agency reported. He apparently transmitted photos to his brother and to the township chief showing the paramilitary troops massing equipment on the Hong Kong border with mainland China, the agency said. The drills conducted in neighbouring Shenzhen fuelled speculation Beijing might deploy the People’s Armed Police to quell the unrest in Hong Kong. Lee was part of a volunteer group for Fangliao township, a fishing community in Pingtung county, southern Taiwan. Fangliao’s mayor Chen Ya-lin said Lee was expected to fly from Hong Kong to Indonesia to meet him in Jakarta on Tuesday, but he had failed to show up. The case was reported to the Mainland Affairs Council on Sunday. “I kept hoping he might have lost his phone and that we would still meet in Indonesia, but he did not show up,” Chen said by phone on Thursday. “We are definitely very concerned. In the past, Lee has always travelled independently anywhere in the world, so we were not worried in the past. But this time, we have lost touch for so long.” Chen, who has been directly in touch with Lee’s younger brother, said he feared there was a strong likelihood that Lee was detained in Shenzhen in relation to his support for the ongoing protests in Hong Kong. The city has seen 13 weeks of anti-government demonstrations that have at times turned violent as protesters and police clashed. The unrest was triggered by a now-shelved extradition bill that would have allowed criminal suspects to be sent to mainland China for trial. Chen said Lee had long paid close attention to Taiwan’s current affairs and shared information about the Hong Kong protests on social media. “This happened in particular at a time when the protests are at a climax,” Chen said. “Given the record in China of people being detained, Lee may face some charges. Of course, right now we are not clear if he has been detained, but the possibility is high.” Shenzhen police told Lee’s family members that they did not have a record of him entering Shenzhen despite claims by Lee’s friends that he had dined with them in the city, according to Chen. Shenzhen police declined to answer media requests by phone and did not respond to faxed questions. China’s opaque criminal legal and judicial system has been an issue at the heart of concerns over Hong Kong’s extradition bill. As protests in the city continue, many people have reported having their phones checked or facing additional questioning when crossing into Shenzhen from Hong Kong. British consulate trade officer Simon Cheng Man-kit, 28, a Hong Kong citizen, was held under administrative detention for 15 days when travelling back from Shenzhen to Hong Kong after a business trip in mainland China earlier this month. Shenzhen police said he had violated public administration laws by “soliciting prostitution”, a charge his family denied. In another recent case, Taiwanese rights activist Lee Ming-che disappeared in March 2017 on a trip to the mainland and surfaced at a court hearing in the central city of Changsha, Hunan, in September that year. The 44-year-old activist, who had discussed democracy with mainland Chinese on social media, was sentenced to five years in prison for his activities.