More than 100 fake 10,000 yen bills have been found across the country among the New Year's monetary offerings at shrines and temples and in the shops and stalls lining their pathways.
According to police, at least 125 bogus bills had been found by Monday. Some were at Meiji Jingu Shrine and Sensoji Temple in Tokyo.
Other shrines hit were Ikuta Shrine in Kobe; Chusonji Temple in Hiraizumi, Iwate Prefecture; Sumiyoshi Taisha in Osaka; Kiyomizu Temple, Inari Fushimi Shrine and Heian Jingu Shrine in Kyoto; Takekoma Shrine in Iwanuma, Miyagi Prefecture; Osaki Hachiman Shrine in Sendai; and Terukuni Shrine in Kagoshima.
It is a custom to visit shrines and temples during the New Year's holiday to wish for good luck for the year. The period also sees stalls offering snacks, drinks and other goods set up along paths leading to major places of worship.
Police investigations found that the fake bills did not have the watermark that real notes carry, and in most cases the bills at one location all bore the same serial number.
The Bank of Japan issued new 10,000 yen notes in November, but all of the counterfeit notes mimic the old bills, police said.
Investigators said it is highly probable they were printed on color copiers, and police around the country have launched investigations.
In the case of the two shrines in Miyagi Prefecture, police said they suspect that all 45 fake bills found were used by the same party, because they all bore the same serial number.