The bunkers in Warzone are now openable with the key cards dropped from loot boxes. These key cards have been in the game for awhile now, dropping from loot boxes without any real use, until now.
You can find red access key cards all throughout the map and dataminers have recently discovered blue and green key cards, but it is unsure what those are for yet.
How to Open Bunker in Warzone
Once you have your red key card, make your way to any of the bunker doors around the map and look for the keypad around the entrance. Go up to the keypad and interact with it and the doors should slowly start to unlock granting you and your squad entry. Enter and be met with a surplus of loot boxes and another bunker door that is unable to be unlocked by the red key card. Could this be what the blue or green key cards or for?
The clip below posted to Reddit by u/AlexShadowMere shows just exactly what the bunker looks like.
Personally, unless they plan to make key cards rarer, the level and amount of loot in these bunkers are a little underwhelming. Loot isn't terribly hard to come buy in this game and getting loadouts isn't the most difficult. Maybe putting a buy station in the bunker with purchasable items limited only to buy stations in the bunker could be an interesting addition. Or buying back teammates from the buy station will immediately spawn them rather than parachuting them down.
Maybe behind the next door in the bunker is all our wildest dreams.