TOKAMACHI, Niigata Pref. -- Uninformed visitors to Tokamachi might be forgiven for thinking the small, central Niigata Prefecture city has a problem with UFOs.

An entertaining explanation for the aerial invasions -- reportedly less common in winter when deep snow makes for perilous landing conditions -- can be found at a local sushi restaurant.

Chef Fumihiko Kobayashi exchanges his knife for a flat object carved in the shape of a popular "Pokemon" character and hurls it above the heads of sushi-munching customers.

Before you have chance to wonder if he's disposing of some unwanted souvenir, Pikachu glides gracefully around a pillar at the end of the bar before doubling back to Kobayashi's outstretched hand.

With a satisfied smile, he replaces the object on the bar next to an array of similar items -- one represents an octopus, another a crocodile -- and returns to slicing thin slithers of tuna.

"It doesn't always go that smoothly," he said.

Welcome to Matsuzushi -- sometimes known as "boomerang-zushi."

While Tokamachi is famed for being home to Japan's oldest snow festival, to some locals it's Japan's boomerang Mecca.

In addition to Matsuzushi, whose boomerang-lined walls give it the appearance of a boomerang museum, the city boasts one of the nation's first boomerang associations and a high school junior who recently took third place at the world boomerang championships in Australia.

Yoshiyasu Murayama, 16, first succumbed to the boomerang bug on a visit Down Under, and on his return to Japan he decided to pay Kobayashi a visit.

"The restaurant is famous around here," Murayama said.

Kobayashi offered to teach Murayama how to throw the boomerang and invited him to join the city's boomerang association, which was set up by Kobayashi and two friends four years ago with a rather enterprising objective.

"At the time, there was talk about the boomerang being included as an event at the Sydney Olympics," Kobayashi explained. "We thought that if it's given the all-clear, who's going to represent Japan?"

The association quickly found itself with some 30 members -- even though the idea to include it as an Olympic discipline was eventually rejected.

"It's a shame," Kobayashi lamented. "After all, the Olympic torch is in the shape of a boomerang."

Its inclusion at the Games this summer would no doubt have had sports purists wondering if indeed the ancient athletics meet might one day feature tiddledywinks.

But they probably haven't heard Murayama's explanation of the intricacies of the sport.

The boomerang was traditionally a nonreturning, flat curved stick about 1 meter long used by Aborigines for hunting and warfare. The returning type, a later adaptation, was used for imitating hawks for driving game birds into prelaid nets.

Competition boomerangs are much more sophisticated: Some are made from synthetic materials and have a variety of shapes, weights and sizes. The event and weather conditions determine which is used. Murayama owns about 100 boomerangs, the majority of which he made himself.

Murayama explained there are six events featured at the boomerang world cup: "accuracy," "fast catch," "MTA," "Ozzi round" "trick catch/doubling" and "endurance."

In the "accuracy" event, participants are required to hurl a boomerang over 20 meters and get it, on its return, to land on a target marked at the throwing point.

In "fast catch," participants must throw the boomerang a similar distance, catch it upon return and repeat the action five times in as short a time as possible.

The world record stands at 14 seconds.

The aim of the "MTA" (maximum time aloft) event is to keep the boomerang up in the air for as long as possible. Murayama's best time is 39 seconds -- a mere fraction of the world record, which reportedly stands at 14 minutes.

Murayama's appearance at this year's world cup in Melbourne, which featured some 120 participants from 12 countries, including eventual winner the United States, and Germany, the runnerup, was the first by a Niigata native.

But the boomerang has a more personal meaning for Murayama.

Unable to get on well at junior high, he eventually was compelled to quit.

"I hated speaking with people," he said. "I couldn't think of a reason to. Now, thanks to the boomerang, I can."