HBO’s Facebook and Twitter accounts have been compromised in the latest cyber security breach to hit the firm.
A group called OurMine appeared to take control of the main HBO accounts, as well as those for the network’s shows including Game of Thrones.
One posts said “OurMine are here. we are just testing your security”.
It is the latest cyber security headache for the entertainment firm after hackers released Game of Thrones scripts and company data.
Some of the social media posts were removed quickly afterwards.
HBO did not immediately respond to the BBC’s request for comment.
OurMine has a reputation for hacking high profile Twitter accounts.
Last year it compromised Netflix, as well as Wikipedia co-founder Jimmy Wales, Facebook co-founder Mark Zuckerberg and Google chief executive Sundar Pichai.