They're regularly used to illegally download films and TV programmes, but it seems that users may have to look for alternatives to torrent sites.

Dozens of the file-sharing sites crashed last week after a surge in traffic from people looking to illegally stream the final episode of Game of Thrones.

And while some of the sites have been restored, several, including TorrentProject.se are still offline as part of the major piracy crackdown.

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They're regularly used to illegally download films and TV programmes, but it seems that users may have to look for alternatives to torrent sites. Dozens of the sites crashed last week after a surge in traffic from people looking to stream Game of Thrones (stock image)

WHAT IS A DDOS ATTACK? DDoS attacks are a primitive form of hacking using botnets - networks of computers that hackers bring under their control. They do this by getting users to inadvertently download software, typically by following a link in an email or agreeing to download a corrupted file. These botnets are then used to bombard the servers with simple requests for information carried out simultaneously, causing them to become overwhelmed and shut down. Advertisement

The problems were first noticed by TorrentFreak, a site specialising in file-sharing, on Friday last week.

Dozens of sites, including WorldWideTorrents and 1337x appeared to go down after a huge increase in traffic from people looking to illegally stream the final episode of Game of Thrones.

And TorrentFreak reports that a subsequent distribute denial of service (DDoS) attack compounded this issue, leaving users faced with a 403 error message.

In a post on its website, TorrentFreak wrote: 'TorrentFreak spoke to several torrent site admins who noticed an increase of suspicious traffic which slowed down or toppled their sites, at least temporarily.'

Dozens of sites, including WorldWideTorrents and 1337x appeared to go down after a huge increase in traffic from people looking to illegally stream the final episode of Game of Thrones

The TorrentProject.se website is still be down, and an error message when visiting the site says: 'Access to the websites listed on this page has been blocked pursuant to orders of the high court'

WORLD'S MOST PIRATED TV SHOWS OF 2016 1) Game of Thrones 2) The Walking Dead 3) Westworld 4) The Flash 5) Arrow 6) The Big Bang Theory 7) Vikings 8) Lucifer 9) Suits 10) The Grand Tour Source: TorrentFreak Advertisement

While some of the sites seem to have recovered and are back online, others appear to still be having issues.

The TorrentProject.se website, one of the most popular torrent sites, is still be down, and an error message when visiting the site says: 'Access to the websites listed on this page has been blocked pursuant to orders of the high court.'

This suggests that copyright holders have reported the site for streaming content illegally.

TorrentFreak added: 'The above shows that the torrent ecosystem remains vulnerable.

'DDoS attacks and domain issues are nothing new, but after the shutdown of KAT, Torrentz, Extratorrent, and other giants, the remaining sites have to carry a larger burden.'