On 22 May 2021, a joint counter-terrorism exercise was mounted by the Hong Kong Police Force and two AVSECO special units – the Contingency Response Unit (CRU) and the AVSECO Canine Unit (ACU) - at Airport Express Lane platform, Level 6, Terminal 1, Hong Kong International Airport. The exercise enhanced the interoperability and cooperation of the relevant stakeholders in response to counter-terrorist incidents.