Pet fish playing a video game in Japan managed to log on to the Nintendo Switch store, change their owner’s avatar, set up a Pay Pal account and rack up a credit card bill.

Mutekimaru had previously installed sophisticated motion detection tracking software in fish tanks, enabling the fishto remotely control a Nintendo Switch console.

But the technology, and the fishes’ apparent mastery of it, led to an unexpected turn of events earlier this month while Mutekimaru was live-streaming a game of Pokémon.

Mutekimaru had stepped away for a break when the game crashed due to a system error and the console returned to the home screen.

During the next seven hours, the fish reportedly managed to change the name of their owner’s Switch account before twice logging into the Nintendo store, where users can purchase games and other downloadable content.

They also managed to “check” legal terms and conditions, downloaded a new avatar and even set up a PayPal account from the Switch – sending an email out to their owner in the process, video from the livestream appeared to show.