Cụ Rùa, Vietnam’s national turtle, has died.

Hanoi’s own sacred celebrity is thought to be one of the last remaining Hoàn Kiếm turtles (Rafetus leloii) in the world – although outside of Vietnam, many scientists classify these individuals as synonymous with the Yangtze giant softshell turtle (Rafetus swinhoei).

After the death of Cụ Rùa, meaning “great grandfather turtle,” there are just three Hoàn Kiếm turtles left: two in a zoo in China and one in a different lake in Hanoi.

The 200-kilogram (440-pound) freshwater turtle lived in the waters around Turtle Tower (Tháp Rùa) on Hoàn Kiếm Lake, Hanoi.

Tim McCormack of the Asian Turtle Program spoke to the Japan Times, describing the turtle as “possibly the rarest species on the planet and definitely the rarest turtle species... It’s a great blow. It was clearly an ancient animal, I would say easily over 100 years old.”

Vietnam mourns legendary 'grandfather' turtle - @TheAgentBadger explains https://t.co/NrsNVNKgrI #WATO pic.twitter.com/HdL5oGztez

— The World at One (@BBCWorldatOne) January 20, 2016

These turtles play a sacred role in Vietnamese culture. According to legend, the 15th-century emperor Lê Lợi was given a magical sword by the Golden Turtle God, which the emperor used to help gain Vietnam’s independence from China. The tale says, whilst sailing on Hoàn Kiếm Lake, a turtle stole back the sword and returned it to the Golden Turtle God.

Since then, the lake and the turtles have been seen as a symbol of Vietnam’s resilience and a sign of good luck. Vietnamese social media has been filled with homages and eulogies, the Japan Times reports.

“I feel empty. My children, grandchildren will only know the turtle from legend,” an online commentator posted on an VNExpress article.