Three laptops stolen from a high-security immigration control area in Chek Lap Kok airport are still missing more than two weeks later.
The Immigration Department laptops were used in immigration control at the airport and contained the personal data of 3,000 travellers deemed dubious.
About 40 immigration officers were put under investigation after the computers went missing in the middle of last month. Police say checks are still ongoing and no arrests have been made.
Police have said they suspect the theft was an inside job.
The devices were taken from a locked room that was restricted to only four teams, each comprising nine immigration officers. The laptops were last seen plugged in for recharging on October 16.
It is understood that the data included the scanned passport images of passengers who had been targeted while in transit.
Meanwhile, the government stressed the importance of tightening cybersecurity to combat growing online theft and other crimes.
Secretary of Security Lai Tung-kwok said yesterday that security was highly valued for all government computer systems.
"We are working with different departments to upgrade our system security, especially for the protection of personal data," he said.
The minister declined to discuss concrete measures.
Earlier this year, the police announced that a cybersecurity centre would be set up by the end of the year.
"The centre will monitor and screen only data flow, not data content," Police Commissioner Andy Tsang Wai-hung said in response to concerns about privacy and state surveillance.
Twenty-seven officers will work in the centre, including a chief inspector and three senior inspectors.
The police recorded 1,299 technology-related crimes in the first half of this year, a 41 per cent rise year on year.