Three virtual critters appeared in Holland Village on Monday afternoon on the Pokemon Go game app that public relations manager Khairul Sufiyan, 30, downloaded on his Apple iPad tablet.

But the game - about catching such digital creatures called Pokemon, based on a player's location - is not officially available in Singapore. Details on its launch here for iOS and Android devices are scant.

Even so, Mr Khairul, like other eager fans of the hit game series, downloaded the game using a United States Apple account on Monday. The game did not work for him initially, but for about an hour, it became playable. It became unplayable again after that.

Said Mr Khairul: "I refresh the game once a day to check if it's working. This game can become a social activity. Maybe families can go on walks and catch Pokemon."

The game has created such a stir that a Facebook group has been set up by the local Pokemon fan community. The public group, called Pokemon Go Singapore, has about 14,400 members. Users post updates about the game there.

Another fan, university student Hu Yang Tao, 21, who downloaded the US Android version of the game last week but cannot get it to work, said the game is "exciting" because he could bump into another player trying to catch Pokemon in the same area he is in.

"(The game) uses your country's map so that's a cool novelty factor."