A dead whale has washed up off the coast of Denmark, fueling speculation that it could be Timmy, a humpback whale rescued earlier this month in a £1.3million operation.

Timmy – whose health had severely deteriorated after being stranded near Germany since March – was released on May 2 after being transported in a water-filled barge by rescuers.

But just days after Timmy entered the North Sea off Denmark, and following a lack of tracking data, the German Oceanographic Museum determined he didn’t survive the transition to deep water. 

And now, the Danish Environmental Protection Agency has revealed that a whale, likely dead for some time, was spotted off the island of Anholt.

A warden with the agency told Danish TV that the whale is probably a humpback, and 10-15 metres long.

Locals have been warned not to approach the animal, as there is a risk it may explode due to the accumulation of gas inside the body. Dead whales can also carry diseases.

Local news outlet Ekstra Bladet reported that tissue samples will be taken from the whale on Friday.

Scientists had disagreed with the mission to save Timmy, insisting he was unlikely to survive rescue attempts due to his health and the more ethical approach would be to let him die peacefully.

A dead whale has washed up off the coast of Denmark, fueling speculation that it could be Timmy

But a motley crew of veterinarians and rescuers, spurred on by the national frenzy in Germany to save the whale, wouldn’t take no for an answer despite fierce warnings.

The rescue effort was privately funded by two millionaires, MediaMarkt co-founder Walter Gunz and horse racing entrepreneur Karin Walter-Mommert, who said they were prepared to pay ‘whatever it costs’ to release Timmy.

The creature has been described as lethargic and covered in blister-like blemishes, and parts of his mouth were believed to be caught in a fishing net.

Timmy first became stranded on a sandbank in Wismar Bay near the city of Lübeck nearly six weeks ago.

As his health deteriorated, German authorities abandoned attempts to save the mammal, insisting he could not be freed.

But following a spike in national interest surrounding Timmy – with supporters baking whale-shaped cakes and having themselves tattooed with images of the mammal – officials were persuaded to approve the privately-funded operation.

Initial attempts to save Timmy, involving inflatable cushions and pontoons, were unsuccessful, but divers eventually managed to coax the whale onto a flooded barge, towed by the Fortuna B ship.

The whale left the barge in the North Sea at around 8.45am local time on May 2, and was later observed blowing through its blowhole and swimming freely ‘in the right direction’, according to Walter-Mommert from the rescue mission.

And hope was still alive days later when the whale’s GPS tracker apparently sent several signals in the morning, indicating that Timmy had surfaced from the water to breathe.

But experts now believe the GPS transmitter was faulty, lacking the necessary capabilities to detect signs of life, and Timmy’s fate seems far less certain.

Attempts to save the mammal had been criticised by the International Whaling Commission (IWC) as ‘inadvisable’, with experts saying the creature ‘appeared to be severely compromised’ and was ‘unlikely to survive’ attempts to move it into deeper water.

The stranded humpback whale was freed on Saturday following a rescue mission that cost £1.3 million

Continuing to try to save the creature amounted to ‘pure animal cruelty’, according to the director of the Oceanographic Museum in Stralsund, Burkard Baschek.

‘A rescue attempt … is no longer worthwhile … this has been confirmed to us repeatedly by international colleagues,’ he warned prior to the mission.

Thilo Maack, a marine biologist at Greenpeace, said earlier this month: ‘I believe the whale will die very soon now. And I would also like to raise the question: What is actually so bad about that?’ 

‘Yes, animals live, animals die. This animal is really, really, very, very, very sick. And it has decided to seek rest.’

The Danish environment ministry has told the German TV broadcaster Deutsche Welle it was not planning to rescue Timmy if he becomes stranded again, describing whale beaching as a ‘completely natural phenomenon’.