11.   The bank said the false banknotes were smaller in size and lacked water mark images of the crested crane and the security thread.

12.   The fake bills lacked certain identifying features such as holograms and metal security threads which are aimed at making more difficult counterfeiting of the common currency, Mori said.

13.   The euro has elaborate holograms and security threads.

14.   The security thread is a dark line running through the note that can also be seen when held up to light.

15.   They include invisible ink drawings that respond only to ultra-violet light, pages sensitised to disclose chemical tampering and a red, blue and green fluorescent security thread.

16.   Vertical security threads are also woven into the bill.

17.   The bill contains a watermark, security thread and special ink which appears to change colour when viewed from different angles, he said.