A crusader for victims of the Tiananmen crackdown was among three Hongkongers arrested yesterday on suspicion of shutting down three government websites.
Police said the suspects - two men aged 31 and 20 and a 15-year-old boy - were involved in the attempted 'distributed denial of service' attack.
This involves hackers making a computer, network or website unavailable to users, often by flooding it with service requests.
The three were suspected of using a computer with criminal or dishonest intent.
They were released on bail pending further investigation and were ordered to report to the police next month. It is unknown which three websites were affected in last month's attack, which disabled the sites only briefly.
The 20-year-old suspect was believed to be a People Power member, indentified by two fellow party members as Chung Sin-yan.
Chung is administrator for a Tiananmen-focused Facebook group called Never Forget 8964 and is understood to be planning to stand in the September Legco elections.
Yesterday, the operator of a personal Facebook page that is believed to be Chung's hit out at authorities, saying the arrest was politically motivated.
He said: 'I believe this is totally political repression, which I think is aimed at removing the information about social-movement activists and our communications record, on trumped-up charges.' Chung could not be reached for comment.
The officers seized computers and a smartphone from the suspects' homes. The computers are believed to have contained the contact lists of activists in Hong Kong and on the mainland.
They also contained electioneering information about the upcoming Legco polls.