Investigators must be given power to demand secret digital keys from suspects to search encrypted online documents and transactions for criminal evidence, police specialists said yesterday. Hilton Chan Kwok-hung, chief inspector and head of the computer-crime section, said the Electronic Transaction Bill, now before the Legislative Council, should include powers to seize suspect electronic documents. 'Criminals can use encryption to send messages for crimes from money laundering to sending coded triad messages,' he said after an Internet security conference. 'Without the digital keys, such documents cannot be decoded for evidence.' The warning came as the University of Hong Kong computer scientists were set to release Internet encryption software for the Post Office, which will set up the Certification Authority next month to conduct online business transactions. The university's encryption software is so sophisticated that, had it been developed in America instead of locally, it would have been restricted under US laws limiting technology exports. But the software, which would be open to the public, could be exploited by criminals to transfer coded messages which existing police computers would find almost impossible to crack. A Legco bill is expected to pass before the end of next month, giving the same legal status to online documents as to physical documents, but it contains no reference to the police's power of seizure. Sin Chung-kai, a Democratic Party legislator for the information-technology sector, said the police request for more power had no support and existing anti-crime laws could cover the problem. 'The police have not even convinced the relevant government departments to put that in the bill,' he said. However, police and ICAC officers will be getting training on how to hack into computer systems next year in a new course on computer forensics developed at the Hong Kong University of Science and Technology. The head of the university's Cyberspace Centre, Professor Sam Chanson, said the course would involve lessons on code-breaking, hacking and other online investigative techniques. In the first nine months this year 138 hacking cases were reported to police compared to just 13 in all of 1998.