An unaired episode of Game of Thrones has appeared on the internet this morning. Episode 6, due to be aired on Sunday, appeared first on file-sharing sites and a Reddit post. Reddit users spotted that the episode was accidentally aired by HBO Nordic in Spain for an hour before it was removed. The episode 6 appearance follows a similar leak of episode 4 around two weeks ago.

The previous leak was related to a distribution partner in India, and HBO has confirmed to The Verge that the company accidentally posted it on its own platforms. “We have learned that the upcoming episode of Game of Thrones was accidentally posted for a brief time on the HBO Nordic and HBO España platforms,” says a HBO spokesperson. “The error appears to have originated with a third-party vendor and the episode was removed as soon as it was recognized. This is not connected to the recent cyber incident at HBO in the US.”

HBO was subject to a security breach last month, allowing hackers to reportedly obtain 1.5 terabytes of stolen data from the company’s US servers. This latest leak is not related to the security issues, and hackers have so far only published published script outlines on the web, rather than full episodes.

HBO has struggled multiple times with Game of Thrones leaks in the past. The first four episodes of season 5 leaked online, thanks to advance screeners that are sent out to members of the press. A HBO subsidiary also released a season 6 episode a day early. HBO decided to scrap screeners for season 7, but that hasn’t prevented two major leaks this season.

Update August 16th, 8:45AM ET: HBO comment added to article.