UPDATE: Eagle-eyed fans have pegged the below images as being of Solid Snake mentor Big Boss, whose 1970s exploits were chronicled in previous Metal Gear Solid installments.
You can just about make out the strap of his eye-patch and the Militaires Sans Frontičres logo on his arm.
Hideo Kojima previously stated he'd like to return to the character for "Metal Gear Solid 5", and had ideas for a game involving the World War Two Normandy landings.
"Metal Gear Solid 4 wrapped up in 2008, and the dev team took post-project time off right after that," Kojima said last year. "But, of course, we were in a situation where we had to start planning for MGS5. So I started coming up with several ideas.
"I had several ideas for a game featuring The Boss and the Cobra Unit during the invasion of Normandy. I then handed these plans over to the team so they could take over and make the game."
ORIGINAL STORY: Metal Gear Solid: Ground Zeroes has been revealed by series creator Hideo Kojima.
The franchise boss unveiled the new title during an event marking the 25th anniversary of the Metal Gear series.
Ground Zeroes runs in the new Fox Engine. Twitter reports from the event state that real-time footage of the game was shown in action, leaving many in the audience suitably impressed.
"Well other people are talking about it so... next Metal Gear shown, and it looks F***ing HOT," one user wrote.
"Snake crawled, avoiding searchlights, killed guard, rode jeep, called in helicopter for evac," said another. "Sounds like Metal Gear, but the scale & atmosphere... Wow."
The demo was reportedly running on PC at current-gen specs, according to a third person in the audience.
The section ended with the player being airlifted to safety in a helicopter playing Ride of the Valkyries, Famitsu added.
Kojima also used the event to confirm a Metal Gear Solid film, to be produced by Marvel producer Avi Arad for Columbia Pictures.
Metal Gear Solid: Social Ops, a mobile game for GREE was also shown.
Hideo Kojima is set to speak in public again at the Eurogamer Expo next month. We're very excited.