On the evening of 5 August 2021, Customs officers intercepted a 47-year-old man in Yuen Long and searched a nearby three-storey village house on Tai Shu Ha Road West, finding a suspected cannabis growing den.[1][2] They seized 1,043 suspected cannabis plants weighing about 460 kg, about 5 kg of suspected cannabis buds, and growing equipment including solar lamps, ventilation units and carbon dioxide generators.[1][2] Customs valued the seizure at about HK$70 million and called it the largest cannabis growing-den case it had detected.[1][2]

The man was arrested, and officers said further arrests were not ruled out.[1][2] Customs said the den had been running for only three to four months and its plants had not yet been harvested, estimating it could have produced up to two tonnes of cannabis a year worth about HK$270 million.[2]