The Tokyo Metropolitan Police Department has arrested a former employee for stealing cash and other items from a MUFG Bank customer's safe deposit box.

The suspect is 46-year-old Imamura Yukari, who worked in manager-level positions at the Nerima and Tamagawa branches of the financial institution.

According to police, Imamura is suspected of stealing about 20 kilograms of gold bullion with a total market value of 260 million yen ($1.6 million USD) around September last year.

Imamura is believed to have used the customer's spare key to gain access to the box, selling the bullion at a pawn shop and using the money for FX investments and others. 

Police are continuing their investigation, as it appears that over a 4.5-year period, Imamura stole from the safety deposit boxes of about 60 bank customers.

Imamura has admitted to the theft of 20kg of bullion.