The recent theft of more than ¥85 million in cash from a safe at a police station in the city of Hiroshima was likely an inside job, investigators said Wednesday.

The police are looking at the possibility of an inside job as the safe could only be opened with the approval of the chief of the Hiroshima Chuo Police Station or the head of the station's accounting division.

The ¥85.72 million ($760,000) in cash was being kept in the division safe as evidence for a fraud case. A police officer noticed the money was missing around 8 p.m. on Monday, according to the police.

Located on the first floor of the station, the division is locked during nighttime and holidays, and only a handful of people at the station knew there was a huge amount of cash in the safe.

The police said monthly inspections are carried out by more than two people at a time but declined to say when the most recent inspection took place as it could hamper ongoing investigations.

The station is located in the center of Hiroshima, next to the prefectural police headquarters.