Japan's Mizuho Financial Group Inc. said Thursday that Yasuhiro Sato will quit as the head of its core banking unit Mizuho Bank on April 1 and Vice President Nobuhide Hayashi will take the post, according to local media.

The group went on to say that Sato will stay as president of the Mizuho Financial Group, according to Japan's Kyodo News.

The announcement came after the financial group was punished last month by the Financial Services Agency over the bank's involvement in transactions with members of organized crime groups.

Mizuho Financial Group said last month that its Chairman Takashi Tsukamoto will step down from his post on March 31 to take responsibility for failing to properly manage the bank, reported local media.