PARIS — A beluga whale stranded in the Seine river in France has been lifted from the water in the first stage of an ambitious rescue operation.

The four-meter (13ft) whale — a protected species usually found in much colder Arctic waters — was stuck in the river, northwest of Paris, for a week.

A dozen vets were waiting on a barge to treat the whale after it was hoisted out the water in a sort of hammock.

About 80 people are involved in the rescue, including divers and police.

It took the rescue team nearly six hours overnight to lift the ailing whale, which weighs 800kg, out of the water and onto a barge.

Rescuers are moving it onto a refrigerated truck that will take it back to the coast. They will then hope to treat the animal for several days before releasing it back into the open sea.

"It's a long rescue operation, very technical, which required many skills," said Isabelle Dorliat-Pouzet, secretary general of the Eure prefecture.

The beluga was trapped more than 100km (62 miles) inland and its health deteriorated after failing to eat.

Animal specialists are on constant standby during the move.

"There may be internal problems that we can't see," said an expert from the Marineland sea animal park in southern France — although she added that belugas are "extremely hardy" as a species.

People gathered on the banks of the river at Saint-Pierre-La-Garenne in Normandy to watch the rescue — as interest in the whale's survival spread beyond France.

So far rescuers have tried to feed the whale frozen herring and live trout to stimulate its appetite and help it make the long return journey back along the river out to the English Channel — but the whale has not turned around.

Experts are puzzled how the whale managed to stray so far south from its natural habitat.

Belugas occasionally venture south in the autumn to feed as ice forms, but it is rare for them to travel so far from their native home. According to France's Pelagis Observatory which specialises in sea mammals, the nearest beluga population is off the Svalbard archipelago, north of Norway, 3,000km (1,870 miles) from the Seine.

But similar stories are not unheard of. In May, a killer whale was found dead after swimming up the River Seine in Normandy. And in 2019, a dead whale was found in the River Thames near Gravesend, UK officials said. — BBC