Game Of Thrones broadcaster HBO has sent "take down" notices to Periscope, the Twitter-owned live-streaming video app, after users broadcast new episodes of the hit show as it aired on TV.

The US broadcaster has criticised the app for not doing enough to spot piracy and copyright infringement, as the much-anticipated fifth series of the TV series began in the US on Sunday night, and Europe on Monday. Twitter maintains that Periscope complies with US copyright law.

Periscope is a free app that enables users to broadcast a live stream from their smartphone camera of anything they wish.

In a statement, an HBO spokesman said: "We are aware of Periscope and have sent take down notices.

"In general, we feel developers should have tools which proactively prevent mass copyright infringement from occurring on their apps and not be solely reliant upon notifications."

The issue is that while Periscope's terms and conditions note that users should respect intellectual property, it relies on notifications from users to alert them when breaches occur, and Game Of Thrones fans who do not have access to the TV channels involved appear unlikely to give up on a way of watching the show. However, Periscope is able to delete a user's account if they are found to have infringed copyright.

Game Of Thrones has recently been revealed to be one of the most pirated TV shows in the world - with more than one million downloads of the first episode of series five, which was leaked ahead of its US premiere. File sharing site TorrentFreak reported that one in ten of those downloads came from Britain, as users aimed to see it ahead of its TV debut.

The site's editor, Ernesto Van Der Sar, said it was "without doubt one of the most prominent leaks in TV history". However Mr Van Der Sar added that this meant Periscope was not a major concern for HBO.

"In my view, Periscope is a non-issue (for Game Of Thrones) because the show is already posted online at very high quality on several other services," he told the BBC.

Mr Van Der Sar suggested that the total number of downloads of Game Of Thrones episodes from torrent sites across the show's history was likely to be in the "hundreds of millions".

"But mobile live streaming could be more of an issue for live sporting events like football matches," he added.

There have already been reports on social media of football fans using the app to live stream games from inside stadiums to fellow users, with some taking to social media to confirm the presence of broadcasts of Premier League games.

The Premier League is looking to crack down on social media breaches - with six-second video app Vine also widely used to upload clips of goals from games - in the wake of a new TV deal worth over £5 billion.