NAGANO -- Just as some venues for the Olympics were taking shape last June, six of Ramilo DeLeon's friends suddenly ended up in police custody after a crackdown on illegal immigrants.

Since that day, DeLeon, a Filipino construction worker, has spent several sleepless nights worrying about another sweep. Fearing police, he closeted himself in his apartment, leaving home only for work. "(The foreign workers) have worked very hard for years to prepare Nagano for the Games. But once our work was done, we were thrown away like toys," said DeLeon, 29, who lost his job in December and has yet to receive his pay for the month.

Last year, Nagano Prefectural Police arrested or deported 397 foreigners, conducting 13 raids at homes of illegal foreign workers and related locations as of November. The arrest figure nearly doubled from the previous year, citizen groups claim, criticizing police for violating the rights of foreign workers by stepping up the crackdown after exploiting their labor for years.