This Sunday's episode of 'Game of Thrones' has leaked to the pirating public

Update 8/4, 10:30 am ET: An HBO source confirms to Mashable that this episode leak is not part of the HBO hack from earlier this week.

"This confirms the compromise of episode 4 of Game of Thrones Season 7, earlier this afternoon," a spokesperson for HBO distribution partner Star India said in a statement.

"We take this breach very seriously and have immediately initiated forensic investigations at our and the technology partner’s end to swiftly determine the cause. This is a grave issue and we are taking appropriate legal remedial action."

Previously: You can now watch Sunday's Game of Thrones episode a few days early.

Days after reports that hackers had broken into HBO systems, the upcoming episode of the mega-popular fantasy show has shown up online. The episode, Season 7, episode four, entitled "The Spoils of War," appeared on the subreddit r/freefolk, a popular Game of Thrones discussion board that is not moderated.

Reddit user zmax87 posted it early Friday morning and said in the comments that it was a "Gift from Pakistan."

Previously, it was unclear if the HBO hack had resulted in the theft of any unaired full episodes of Game of Thrones. It was reportedly known that scripts had leaked along with upcoming episodes of Ballers and Room 104.

According to Entertainment Weekly, the supposed hacker of Sunday night's attack sent out the following, anonymous email to many reporters: 

"Hi to all mankind. The greatest leak of cyber space era is happening. What’s its name? Oh I forget to tell. Its HBO and Game of Thrones……!!!!!! You are lucky to be the first pioneers to witness and download the leak. Enjoy it & spread the words. Whoever spreads well, we will have an interview with him. HBO is falling."

It remains unclear whether any other future episodes will be leaked.

This isn't the first time that HBO has suffered leaks to its most popular show.