The suspects include five males and four females, aged between 15 and 39. Six are secondary school students.
Others are a teacher, an unemployed person and a management-level university employee.
They are accused of conspiracy to perpetrate terror with the intent to cause serious harm.
The police say the ring planned to bomb Hong Kong courts, the Cross-Harbour Tunnel and railway stations.
An explosives laboratory, air-guns, protective and communications equipment were found in a hotel room in a popular shopping district.
The suspects are believed to be members of a self-proclaimed revolutionary group, “Returning Valiant’.
Steve Li of the Police National Security Department told reporters that they had a good division of labour.
The Senior Superintendent said while some provided money, some are the scientists – the ones who made the bombs.
“One is responsible for the sourcing of chemicals and other materials needed for the plan. Another small group of people creates the bombs, using chemical equipment.
“There is also a surveying team and an action team, which is responsible for laying the bombs”, Li disclosed.
The police uncovered manuals and about 80,000 Hong Kong dollars ($10,300) to be used to abscond after the attacks.
Bank accounts with the sum of HK$600,000 linked to terrorist acts have been frozen.
