Foreign nationals working as ski instructors and guides without valid work visas are raising concerns among local officials and businesses in major winter tourism areas in Japan ¡ª including Niigata, Nagano and Hokkaido prefectures ¡ª who warn that such illegal operations could disrupt public order and create unfair competition.

The number of foreign skiers visiting Niigata reached a record 633,000 last season ¡ª a 112.1% increase from the previous year ¡ª according to the prefectural government, with officials expecting further growth this winter.

In the resort town of Yuzawa, roughly 2,000 foreign nationals are believed to have worked as ski instructors this season without valid work visas, a local government official in charge of tourism told The Japan Times. Many appeared to be Chinese nationals, the official said.