UPDATE 12.10pm UK: Following this morning's leak, Crytek has now officially confirmed Crysis 4.
The developer released the short CGI trailer below just after midday UK time, less than an hour after a social media post spoiled the surprise.
There's little to the trailer other than some flashy effects reminiscent of the series' nanotechnology, and then the phrase: "Join the journey. Become the Hero." But there's now no doubt: Crysis 4 is on its way.
"It's now finally time to confirm - yes, the next Crysis game is happening!" Crytek boss Avni Yerli said today in a blog post. "We are so pleased and excited to bring this news to you, and we really can't wait to reveal more details about what lies ahead.
"Right now the game is in the early stages of development so it will be a while yet, but we wanted to bring you the news at this time as we are so hyped for the future, and to let you know that we will be listening to our community.
"Crytek has a proud history of working with our community to develop the games you want to play. Crysis is incredibly important to so many people - it's beloved by gamers everywhere, and some of those working in the industry today are doing so because of the original game - so we want to make sure the next instalment in the franchise lives up to all of your expectations. Make sure to join our socials and get involved!"
ORIGINAL STORY 11.15am UK: An image which appears to announce Crysis 4 has appeared online, posted by Crytek China.
The image is still visible at the time of writing on Chinese social media site BiliBili.
"The 'Crysis 4' project is confirmed, opening a new nano battlefield!" translated text reads. "Follow @Crytek_Official, we will continue to update you with the latest news."
It's been nine years since the last numbered Crysis game, Crysis 3, arrived for PC, PlayStation 3 and Xbox 360. More recently, remastered versions of the original Crysis and its two sequels have released over the past two years - prompting speculation an all-new entry was up next.
Eurogamer has contacted Crytek for comment.