Hundreds of visitors turned up at Inuka's enclosure in the Singapore Zoo yesterday - the first weekend after the zoo revealed on Thursday that the 27-year-old polar bear could be put down if its health continues to decline.

As the rain pelted down outside, visitors watched as Inuka rested at the far end of its cave, its once limber movements now sluggish.

A health examination on April 3 found that Inuka had a stiffer gait, on top of other health problems like arthritis, dental issues and the occasional ear infection.

It is being given painkillers and antibiotics. Polar bears live an average of 25 years under human care.

"The last time I was here, I saw him swimming around. Now he's just lying there," said financial consultant Lee Wing Wai, 51.

"I don't know when they will put him to sleep. Since it's the weekend, I popped by."