About five or so years ago a Hydrofoil ferry was en-route from Hong Kong to Macau. On board were a considerable number of HK Chinese with wallets bulging ready for their sessions at the Macau casinos. The ferry stopped to help a Chinese fishing boat that was indicating that it was in distress. When the fishermen came on board they produced guns and held up the entire boat. After relieving the passengers of the valuables, mobile phones and disabling the ferry's radios they sped off in their boat up the Pearl river to China.
The Chinese police apprehended them a couple of weeks later. They were tried in Chinese courts so the Hong Kong justice system had nothing to do with it. The two ringleaders were executed and the hangers-on received long prison sentences (probably the worst option).
There has not been any problem on the Hong Kong-Macau ferry route since.