A rare, and nearly 100-year-old turtle, has died in Vietnam, leaving only three of his kind left in the world.

Hoan Kiem Lake in Hanoi, Vietnam.

Hoan Kiem Lake in Hanoi, Vietnam. Image by Stefan Fussan / CC BY-SA 2.0

The giant soft-shell turtle is deeply connected to folklore in Vietnam, in a tale in which a real 15th century Vietnamese emperor, Le Loi, fought for independence with a magic sword, which a turtle later brought into the lake. The deceased turtle was known as Cu Rua, which means “great-grandfather turtle”, reports CNN. The turtle was said to have been spotted floating dead in Hoan Kiem Lake this week and the cause of death has been described as old age and bad weather.

Hoan Kiem Lake in Hanoi, Vietnam.

Hoan Kiem Lake in Hanoi, Vietnam. Image by Paul Arps / CC BY 2.0

The giant turtle weighed 440lbs (200kg) and is critically endangered, reports the Guardian. The turtle was seen only rarely and was considered a sign of good luck. Many people took to social media to express their dismay over the animal’s death.