Nintendo Switch owners are reporting a wave of unauthorised account access attempts, in what looks a significant spate of attacks.
Twitter user Pixelpar, founder of Nintendo fan site LootPots, had his account accessed "numerous times overnight" yesterday from new locations, and received a string of warning email messages alerting him to the breach.
A Eurogamer staff member experienced the same thing on Friday.
Social media and forum posts from fans over the past weeks suggests it is a relatively widespread issue, with accounts accessed from countries such as the US, Chile and Russia.
Several users whose accounts were accessed and who had Paypal linked reported funds being accessed to buy Fortnite's VBuck currency.
Nintendo is yet to acknowledge the problem, but just over a week ago tweeted a notice encouraging fans to enable enhanced verification for their Nintendo Accounts.
The process takes less than two minutes to complete and uses the free Google Authenticator app for iPhone and Android phones. It's a good idea - especially if you have Paypal or any other payment methods linked and are at all concerned.
At the very least, signing into the Nintendo Account website lets you look at your Sign-In History to check the locations you have been logged in. It's under your "Sign-in and Security Settings".
We've contacted Nintendo for comment.