The Jockey Club's new plan for the Central Police Station compound, which includes the digging of a tunnel to link buildings on the site, has rung warning bells among observers about damage to archaeological relics that may be underground. The tunnel would lead to a prison hall that is to be converted into the entrance to a new contemporary arts centre to be built beside it. The club, which says it has conducted thorough conservation studies of the site, held briefings on its plan for professional groups last week and is expected to announce the details publicly today. According to people told of the plan, the club has decided to keep Hall F of Victoria Prison and erect a new building beside it to house the arts centre, with Hall F as its entrance. An earlier plan by the club drew heated criticism because it proposed demolition of Hall F, the only prison hall on the site not designated a monument. It held political prisoners during the Japanese occupation and later housed Vietnamese refugees. The new plan calls for another new building, probably a concert hall, on the site of the prison's laundry block, which is to be demolished. The buildings will comply with the 80-metre height limit set by the Town Planning Board earlier this year. The reduced height of new buildings and preservation of Hall F address public criticisms of the original proposal, particularly its 160- metre observation tower. The club has brought in renowned curator David Elliott as an adviser for the arts centre. Elliot has been director of well-established museums around the world, including the Mori Art Museum in Tokyo. The club aims to provide direct access to the arts centre with the underground passage from behind the barracks block, which dates from 1864. But conservation groups said there may be archaeological features under the compound that could be damaged by the tunnel. 'If there is underground work, the club should tell us how it is going to ensure archaeological relics are going to be protected,' a building professional who attended last week's briefing said. 'I am also not sure that the digging will not affect the structures of the old buildings and change the character of the place.' The club, which has been criticised in the past for a lack of transparency on the project, is expected to explain how it will choose operators for the arts and business facilities. Antiquities Advisory Board member Bernard Lim Wan-fung said preservation of Hall F was welcome but he wondered why new buildings were necessary, given there were more than a dozen blocks on the site. The compound, the earliest law and order centre in the colony, built between the 1840s and 1910s, comprises three monuments: Victoria Prison, Central Police Station and the former Central magistracy. In 2007, the government drew criticism when, without conducting an open tendering process, it announced the site would be leased to the Jockey Club for revitalisation. The club, which is to finance the project, later presented its first plan, a HK$1.8 billion cultural complex. Under public pressure, it scrapped the plan's 160-metre observation tower, designed by Swiss architects Herzog and de Meuron, and went back to the drawing board. The club hired British firm Purcell Miller Tritton to devise a conservation management plan, which was released but is no longer available on the government or club websites. The club is expected to launch another round of public consultation on the latest design. It has appointed Asia Art Archive executive director Claire Hsu, who is the stepdaughter of former Jockey Club chairman Ronald Arculli, and former Swire Properties director Michael Moir, who runs a property management and investment consultancy, as consultants on programming. They replace in-house charities executive director William Yiu, who left in January.