Almost three-quarters of a century after being deliberately sunk, Hong Kong's most famous warship may have made a surprise reappearance in the soft seabed of Victoria Harbour.

A statement on March 27 by the Civil Engineering and Development Department (CEDD) that a 40-metre-long metal object had been found buried in the mud close to the old Wan Chai ferry pier triggered a frenzy of speculation about the probable shipwreck's identity.

One Chinese-language newspaper incorrectly identified the wreck as being that of a Japanese merchant vessel. Other media pointed to the possibility that it was HMS Tamar, the steam- and sail-powered troop carrier that had been anchored in the harbour as the British Royal Navy's depot ship for 44 years before being scuttled in December 1941, to avoid capture by the invading Imperial Japanese Army.

It had been assumed that HMS Tamar was salvaged and removed from the harbour after the second world war but since the discovery of the shipwreck, the Hong Kong Maritime Museum has launched an HMS Tamar webpage and district councillor Paul Zimmerman has published his ideas for what to do with the wreck, which he confidently refers to as HMS Tamar, one of which involves preserving sections of it as exhibits on the harbourfront.

Assuming it is the old iron-keeled warship that has rudely interrupted progress of the HK$4.64 billion Wan Chai Development Phase II project, the authorities are faced with a tricky dilemma.

Despite six weeks of what the department calls "further investigation and assessment" no one in government circles is rushing to make a public statement about the shipwreck's identity.

"According to the available information, the concerned metal object may be part of a shipwreck," says a spokesman. "As the investigation and assessment are still ongoing, we are not able to provide any supplementary information for the time being."

If it is HMS Tamar, it is easy to imagine why no one is keen on publicising the fact. This is the ship that not only lent its name to the British naval presence in Hong Kong for 100 years but has also done so to the modern SAR government buildings, the adjacent park, which was occupied by protesters last year in the city's most significant political unrest for decades, and the People's Liberation Army headquarters next door. The authorities will want to be sure of their facts and the CEDD has appointed a team of marine archaeologists to survey the underwater site.

"They should be recording and documenting the site as they have found it - the ship's structure, fittings, what the vessel carried aboard and where they are found in context with the ship's structure, and the condition of the shipwreck," says Dr Bill Jeffery, a founding member of the Hong Kong Underwater Heritage Group and a research associate with the Maritime Museum who has worked on many shipwreck projects around the world.

HMS Tamar is unlikely to be Hong Kong's version of the Titanic, lying on the seabed intact and immaculate, cautions Jeffery: "It was badly damaged in 1941 [when it was sunk] and since then it must have been salvaged for the upper sections to now not be there.

"Identifying it shouldn't be a problem. They will look at historical data as to what happened to Tamar when it was intentionally sunk and what was its last known location."

He also points out that parts of HMS Tamar were constructed of iron, which would distinguish it from most other wrecks, and that any artefacts recovered would have the "Pussers arrow" - a distinctive arrow sign - stamped into them, as did all War Department equipment of the time.

Jeffery thinks he might know the reason behind the government's reticence to decide what to do with the Wan Chai shipwreck.

"There is politics in all heritage issues and this site is no different. Maybe some people think it shouldn't be protected because of this association and what it reminds us of. But it is a fact - this is Hong Kong's history. We just need to be more clever about how we tell this history."

There is also the sensitive legal question of ownership. Could Britain claim the wreck?

Another tricky issue is that, however valuable HMS Tamar might be in terms of heritage and however colourful its story as a feature of Victoria Harbour, it is not defined as an official relic under the government ordinance regarding the protection of local heritage.

Nevertheless, "it [would be] a very significant shipwreck for Hong Kong," says Jeffery. "You can see evidence of this in the Admiralty area, with park, street and area names. We don't need to be told how significant it is, the Hong Kong government have already told us."

IN TAMAR PARK, near the government headquarters, a young woman is sitting, enjoying a quiet lunch as the automatic sprinklers spray water onto manicured grass.

"I know this is Tamar Park but I have no idea what the word means," admits Alexandra Szeto, 19, a student at the nearby Academy for Performing Arts. The trainee opera singer might seem as though she'd be the last person in Hong Kong to be motivated by naval heritage but when she hears about the shipwreck and the speculation that it is probably HMS Tamar, she is surprisingly engaged.

"That is very interesting," she says. "They should take care of this thing because it is our history."

To the east of the government building, a battered placard with a faded image of a yellow umbrella leans precariously against the kerb, marking the remnants of the Occupy protests. Inside a polythene and canvas shelter by the roadside, Man Kit-ku, 33, is one of perhaps 100 die-hard protesters maintaining a stoic vigil. Man started protesting in Mong Kok on September 29 last year and, when not working for a nearby five-star hotel, he keeps watch next to the Tamar building.

"Sorry, I don't know why it is all called Tamar here," he says. "All I know is that the doors to these buildings should be open to citizens but they are closed."

When the rumours about the Wan Chai shipwreck are outlined to him, he considers them carefully, then smiles: "We are also stuck in the mud of the harbour and stuck in the Chinese system, like that old ship."

About 50 metres from the Occupy camp, Alan Kwok Sau-ming is working as a volunteer for the Tung Wah Group, which operates the Tamar Cafe as a successful social enterprise. How much does he know about Tamar?

"Tamar is from the British period and that building," says the retiree, pointing up to the PLA headquarters, "that was for the British Navy. I think Prince Charles opened it," he adds, correctly.

Kwok is well informed and has read in the newspaper about the shipwreck in Wan Chai, but he is not convinced it is the British vessel. But what if it is?

"It's part of the history of Hong Kong and the second world war," he says. "It must be looked after."

LAUNCHED IN LONDON in June 1863, HMS Tamar first arrived in Hong Kong in 1878, bringing relief crews to British ships based in what was called the China Station. In 1897, she formally replaced HMS Victor Emmanuel as the city's receiving ship and was converted from a seagoing vessel to a hulk: a floating accommodation and office block that would be the administrative headquarters for the British naval presence in Hong Kong.

On February 7, 1897, the Hongkong Telegraph newspaper reported: "The Tamar is not completed yet so we hope that her roof will be made water tight and a little ballast added before she takes the place of the old Victor. [Otherwise] she'll roll like a harpooned whale when a typhoon happens along."

HMS Tamar went on to survive many typhoons and the ballast that was added for stability is another means of identification the archaeologists will be using. Her white hull, three masts and distinctive awning roof can be seen in many panoramic photographs and paintings of the harbour from 1897 onwards; the ship remained a permanent feature until the dramatic events of December 1941.

Her final moments are captured in first-hand accounts published by local historian Tony Banham and his website, Hong Kong War Diary. They help recreate the events of December 11 and 12, 1941, when, amid thick smoke, relentless gunfire, civilian panic, air raids and an intensive naval evacuation of Kowloon, Commodore A.C. Collinson ordered the scuttling of HMS Tamar, to avoid the ship falling into enemy hands.

"At 2100 hours ordered to sink Tamar, which had been moved to buoy in the harbour. It was a very dark night with no lights anywhere, so a hazardous operation to fire torpedoes. Apart from trying to avoid junks without lights and harbour buoys I was fired on from Hong Kong side. I fired one torpedo without success …" (11 December 1941. Lieutenant Laurence D Kilbee HKRNVR [Hong Kong Royal Navy Volunteer Reserve], commanding officer of Motor Torpedo Boat 08 (MTB 08).

The torpedo idea was abandoned and instead explosive charges were laid the next day.

"The old Tamar, the wooden ship [had been] taken out of the dockyard on 8th December and we sank her at her buoy on the 12th" (12 December 1941. Commander FW Crowther RN Naval Dockyard).

Unfortunately, the superstructure that had been added to Tamar created an airlock and the old ship remained defiantly semi-submerged as the battle raged. The Royal Artillery had to finish her off, and she finally sank to the bottom, leaving her three masts exposed.

"Later, I was talking to one of the dockyard policemen who had done the job and he told me that it was fantastic to see the number of rats leaving the sinking ship." (Mrs. S Briggs, the wife of a naval officer serving in HMS Scout).

HMS Tamar's final 48 hours remain a source of fascination for military historians but surely they have minimal relevance for 21st-century Hong Kong, forging its place as part of an increasingly confident China?

"Twenty years ago I might have agreed," says Banham, "but today, so many younger people in Hong Kong seem to have realised that the older generations let too much of their heritage slip through their fingers. What little is left now needs to be preserved. That doesn't mean progress should come to a stop, nor that the city's evolution should be constrained: it means embracing our heritage within that evolution."

He notes that the events of December 1941 and their aftermath were "very much multinational".

"The British made up the largest part, with the Indians next. Then came the 2,000 Canadians, and a similar number of local Hong Kong people [either serving with British forces, the HKVDC - Hong Kong Volunteer Defence Corps - or the HKRNVR]. The HKVDC also included Russians, Poles, Danes - I believe 14 nationalities in all. The Canadian contingent also included a few Americans who had crept over the border, and British forces included Australians, New Zealanders, Irish, Canadians and South Africans," he says.

Indeed, Banham's records show the first naval fatality of the Battle of Hong Kong was a native Hongkonger: ordinary seaman Wong Yuk-wah of the HKRNVR lost his life on December 8, 1941.

By 1946, there were 2,000 locally recruited Chinese sailors (known as locally enlisted personnel, or LEPs) serving in all parts of the British Royal Navy, including a new HMS Tamar. When the British forces returned to a devastated Hong Kong in August 1945, the name was allocated to the naval shore station, and that remained the case until 1997. The plaque from the main gate is on display at the Museum of Coastal Defence, in Shau Kei Wan, along with the ship's anchor and other artefacts. The main doors of the Anglican St John's Cathedral, which served as an officer's club during the Japanese occupation, were rebuilt from timber salvaged from the ship.

The name Tamar was integrated into Hong Kong life but the ship had become one of 50 or 60 wrecks that littered the harbour, including those of other British warships scuttled in December 1941, Japanese craft, junks, sampans and many other vessels caught in the conflict. Contracts were issued for the demolition and clearance of wrecks and, on December 20, 1947, the China Mail reported an "underwater attack on Tamar" as she was cleared and salvaged. The remains of the wreck were marked on charts for another 20 years or so, on the very spot where the CEDD was dredging when the so-called metal object was stumbled across.

If the Wan Chai shipwreck is confirmed to be that of HMS Tamar, it is unlikely to be little more than the mangled remains of the keel and some artefacts from the period, but this old scrap is laden with meaning for the city.

"It's certainly not Sutton Hoo - a ship of global archaeological importance," says Banham, referring to a boat used as a burial vessel in the 7th century, in eastern Britain. "Nor is it the Titanic - a human tragedy of metaphorical proportions. It's just an old working ship, the visible base of the Royal Navy in Hong Kong for many years, familiar to thousands of British and locals and the home of many of those lost in the war.

"It's important in the way that much real heritage is: a central part of the story, not of the rich and famous, but of many ordinary people."

This ship's name is deeply ingrained in Hong Kong life and identity, and it's hard to think of a more pertinent symbol of the defiant local spirit. If its distorted remains are confirmed as being those discovered off Wan Chai, the old warship should be treated with all the dignity and respect she deserves.