A sea turtle nicknamed "Piggy Bank" has died after complications from surgery to remove nearly 1,000 coins she swallowed during captivity, Thai vets said Tuesday.

The reptile was thought to be recovering well from the pioneering seven-hour operation earlier this month to remove five kilograms (11 pounds) of coins lodged in her digestive tract -- good luck pennies tossed into the pool she was kept in.

But she took a sudden turn for the worse over the weekend, developing blood poisoning from serious intestinal problems after the coins were removed.

Omsin (Piggy Bank) was 25.

Her plight, recorded in precise detail in daily news updates, captured the hearts of many Thais and raised questions over the collision of traditional beliefs in good luck and animal welfare in the country.

"At 10:10am she went with peace," a tearful Nantarika Chansue, the vet in charge of Chulalongkorn hospital's aquatic research centre, told reporters on Tuesday.

"She is my friend, teacher and patient," she added.

The turtle lived for two decades in a small pond in a public park in Chonburi Province.

Visitors tossed coins into her pond seeking to "make merit" or good luck.

Vets hope the media coverage of the stricken creature will make Thais think twice about throwing coins into ponds where animals live.