For weeks, friends and relatives of a Taiwanese who went missing in Shenzhen after a brief stay in Hong Kong last month have wondered what happened to Lee Meng-chu, aka Morrison Lee, and whether his disappearance in the Chinese city had anything to do with his support for the protests in Hong Kong.

Lee, 44, who hailed from Hsinchu near Taipei, is believed to have been nabbed by Chinese security agents after he was found taking pictures and footage of a drill by China’s military police at the Shenzhen Bay Sports Center, which is just across a narrow stretch of water from Hong Kong.

Taiwan’s Presidential Office and the Mainland Affairs Council have demanded that Beijing give a full account of why Lee has been detained, as nothing has been heard of him for almost four weeks.

In Beijing, the Chinese State Council’s Taiwan Affairs Office confirmed on Wednesday that Lee had been investigated on suspicion of “engaging in criminal activity harmful to China’s national security.” A spokesman said Lee was being detained “in accordance with the law,” without elaborating further.

Some reports say Lee was tracked down soon after he sent photos – likely via WeChat – about Chinese paramilitary troops being massed along the border with Hong Kong to a colleague in Pingtung, Taiwan.

Lee Meng-chu went missing on Aug 20 after entering Shenzhen from Hong Kong. Photo: Handout

Lee is an adviser to a rural government in Pingtung and also sits on the board of the Taiwan United Nations Alliance, an advocacy group for the island’s membership in the UN.

He flew to Hong Kong on August 18 and crossed the border to Shenzhen two days later on a business trip. It is also said that Lee took part in an anti-extradition bill protest while in Hong Kong before entering the mainland, which could also explain why he was held given officials in Shenzhen ratcheted up checks on visitors from Hong Kong as the protests dragged on.

Taiwan is prodding Beijing to provide more details about why and when Lee was detained and where he is being kept, as a cross-strait agreement on mutual judicial assistance stipulates that each must inform the other side promptly when a resident is detained or arrested.

“Beijing and the Shenzhen government should arrange for Lee’s family and a lawyer to visit him as soon as possible to ensure the legal rights he is entitled to,” Taiwan’s Mainland Affairs Council said.

Taiwan’s Straits Exchange Foundation, a de-facto government agency that represents Taipei in cross-strait exchanges, told reporters it had sent three requests to its mainland counterpart, the Association of Relations Across the Taiwan Strait, which represents Beijing, for assistance in locating Lee since he was reported missing on August 20.

Taiwan’s ruling Democratic Progressive Party condemned Beijing on Wednesday, adding what the mainland did would only estrange Taiwanese further and make them more fearful about visiting the mainland.

Chinese military personnel gather at the Shenzhen Bay stadium, across the border from Hong Kong in Guangdong province, on August 15, 2019. Photo: AFP

Previously, Shenzhen police told Lee’s family that they did not have a record of him entering the city via any of the border checkpoints despite claims by Lee’s friends that he had dined with them in the city, according to Taiwan’s Central News Agency and Hong Kong’s South China Morning Post.

“What Beijing’s Taiwan Affairs Office said was an admission that Lee did enter Shenzhen and got arrested in the city on what were likely fabricated charges,” Lee’s relatives said.

In March 2017, another Taiwanese NGO worker employed by the DPP also disappeared after entering the mainland from Macau, and only resurfaced six months later when he was charged and convicted with “subversion of state power”.

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