Questions have been raised after a Hongkonger went missing while on his way to Macau via the mega bridge this month. It turned out Chung Sun-ming was detained by mainland authorities in relation to a mobile phone smuggling case seven years ago. The incident understandably aroused concerns over law enforcement on the Hong Kong-Zhuhai-Macau Bridge . There are precedents in which Hongkongers have been detained upon entering or leaving the mainland in relation to criminal offences. What sets the latest case apart is that Chung was intercepted at a new checkpoint between Hong Kong and Macau. The fact that it came after the government’s ill-fated attempt to enable the transfer of fugitives to the mainland and Macau under the now-withdrawn extradition bill has added to the concerns. No problem with mainland officers holding Macau-bound Hongkonger, says Cheung The perception might have been different had Chung’s detention been made more transparent. The case first came to public attention after Chung’s family reported his disappearance to the media, and later to the police. The detention was confirmed in an official post in mainland social media a few days later, along with an alert to the Hong Kong police under the reciprocal notification mechanism. Whether Chung is guilty of smuggling is a matter for the mainland courts to decide. But he probably did not expect to be arrested while crossing the bridge. He was said to have been detained at a special checkpoint on an artificial island within mainland waters, apparently put in place to beef up security ahead of President Xi Jinping’s visit to Macau last week. The temporary arrangement was announced by the Zhuhai public security bureau early this month but was not publicised by the Hong Kong authorities. Several people on the mainland’s wanted list have since been arrested. Pan-democrats in Hong Kong said the special checkpoint was in breach of the agreement for the three cities each to enforce laws in their own territory. But the government dismissed the accusation, saying the mainland authorities were entitled to enforce their laws within their waters and there was no need to read too much into the incident. But given that three jurisdictions are involved, a more transparent approach would have helped clear the air.