A man pretending to be an administrator of Kyoto Shogin, a failed credit union, on Friday made off with about 100 million yen from the institution's Minami Branch in Kyoto.
The man, who appeared to be around 70, took the cash while the branch manager was counting out 700 million yen, the police said.
A man had earlier called the branch declaring himself to be "administrator Watanabe" and ordered the clerks to prepare cash to be counted by another man he would send, according to the police.
The Financial Services Agency declared Kyoto Shogin, a credit union serving South Korean residents in Japan, insolvent on April 20 and sent in two administrators.