Hackers have stolen what HBO on Monday called “proprietary information” from the company’s computers. Though it has not disclosed what was taken, some news reports say the stolen goods may include new episodes of some series and material related to “Game of Thrones.”

HBO chief executive Richard Plepler reported the breach in an email to employees Monday morning saying that “there has been a cyber incident directed at the company which has resulted in some stolen proprietary information, including some of our programming. Any intrusion of this nature is obviously disruptive, unsettling, and disturbing for all of us.”

Entertainment Weekly quoted an email from unidentified hackers claiming that they had taken 1.5 terabytes of information, including unspecified material from “Game of Thrones.” Reuters reported receiving an email from hackers as well.

One episode each of “Ballers” and “Room 104” had been posted online but no episodes of “Game of Thrones” had appeared, according to Entertainment Weekly. HBO has gone to extraordinary pains to protect the coming plot twists of the popular show from leaking to the public.

The statement from HBO did not detail when the incident happened, and the company declined to comment on reports detailing the material stolen.

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