In a dramatic underwater rescue, Spanish divers have freed a 12-meter humpback whale entangled in an illegal drift net off the Balearic island of Mallorca.

For 32-year-old marine biologist Gigi Torras, the rescue itself and the whale's reaction was her "best ever" birthday present.

"It was actually my birthday when we found the whale so it was the best birthday present ever. Sad but also incredible," Torras said, explaining that it was only the third time that a humpback has been seen in the Balearic Islands.

The weakened whale had been spotted by a ship about five kilometers off the Cala Millor beach in the eastern part of the island, prompting Palma de Mallorca's Aquarium marine rescue center into action.

Rescuers discovered the whale completely trapped in the red fishnet. It could not even open its mouth.

After initial attempts to cut the net from a boat failed, divers from Albatros and Skualo diving centers joined the effort and plunged into the sea to remove the mesh with their knives in a daring 45-minute operation.

READ MORE

Mariupol's last stand
What is monkeypox?
McDonald's leaves Russia for good

"The first 10 seconds she got a bit nervous, but then but I think she knew we were there to help her and she just relaxed and we started working from the front of her mouth backwards," said Torras, who owns Albatros diving center.

"We kept cutting and cutting and she kind of gave a little wiggle to get herself out of it," Torras said, adding that the mammal then stayed for a short while to regain her strength in the company of the four divers and even gave what looked like "a little thank you sign" before swimming off.

Nicknamed the 'walls of death' for the quantity of other sea life they catch alongside their target fish, drift nets were banned by the United Nations 30 years ago.