Reports are claiming that hackers have broken into HBO’s network, obtaining 1.5 terabytes of data. In the process, it is believed they have leaked unreleased episodes from a number of shows (including the script from next week’s Game of Thrones). The group behind the hack have said the material will be released soon.

In an email published by Entertainment Weekly, the hackers wrote: “Hi to all mankind,” they wrote. “The greatest leak of cyber space era is happening.”

“Whoever spreads well, we will have an interview with him.”

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Although unconfirmed, it is believed that the script for the fourth episode of season seven of Game of Thrones, which airs later this week, has been stolen.

HBO confirmed there had been an incident and said: “We immediately began investigating the incident and are working with law enforcement and outside cybersecurity firms”.

“Data protection is a top priority at HBO, and we take seriously our responsibility to protect the data we hold.”

The intrusion was “obviously disruptive, unsettling, and disturbing for all of us,” said chairman and chief executive Richard Plepler in an email to HBO employees.

Richard Stiennon, Chief Strategy Officer at Blancco Technology Group believes events like these will all contribute to the beginning of an all out cyber war.

>See also: Another day, another hack: Deutsche Telekom

“This is a great example of why data governance is becoming so important. Ever since the infamous attack on Sony Pictures, there is evidently an appreciation on the part of hackers for stealing high value content such as movies (Pirates of the Caribbean) and TV shows (Orange is The New Black). Final production videos are a class of information and the theft of such information poses extraordinary losses, if stolen.”

Content producers and all the parties involved in shooting, editing and post-production processing and distribution should be on high alert. They should immediately review their data governance policies and discover the weak links in protecting their content and shore up their defences. An information governance policy should take into account where critical content resides at all times. That content should be protected even when it’s in the hands of third party service providers. To avoid these types of losses, this type of content and all files associated with it should be securely erased when it is no longer required.”