UPDATED 12:36 p.m. ET: HBO confirmed the leak in a statement to Mashable on Sunday.

"Sadly, it seems the leaked four episodes of the upcoming season of Game of Thrones originated from within a group approved by HBO to receive them. We're actively assessing how this breach occurred," a spokesperson said.

That Game of Thrones producer was right to worry about leaks.

HBO's highly-anticipated fifth season of Game of Thrones is getting a premature—and illegal— premiere and fans are freaking out.

The first four episodes of the series started making their way around the Internet Saturday night after being uploaded to several Torrent sites, a day prior to the official Sunday premiere.

The leaks come just one week after Greg Spence, Game of Thrones' post-production producer, fretted about the likelihood of someone uploading leaked footage to the Internet. The show also fell victim to a leak back in January when a cellphone captured its trailer premiere.

The show is no stranger to pirating. In fact, it's the most popular illegally downloaded show in the world.

The four confirmed leaks appear to originate from a screener sent to reviewers ahead of the show's launch. There are four episodes on the screener. The leaked episodes are in 480p, which is equivalent to the quality of standard TV, and a digital watermark is blurred. The show is normally shown in 720p or 1080p through HBO.

The purported leaker noted on a private Torrent tracker that the fourth episode would be the final upload for the evening, although they teased that more may be coming.

Game of Thrones fans that want to wait for each Sunday's episode may have a hard time staying away from spoilers after the leak.

Google's anti-spoiler technology can't get here soon enough.

An HBO representative was unavailable to comment on the leaks late Saturday night.

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