The IDF revealed on Friday, what it described as intelligence showing a Hamas command center located under a the Shifa Hospital in Gaza City. In a briefing, Rear Admiral Daniel Hagari told members of the foreign press corps that there are areas in the hospitals that are used by Hamas to direct its military operations.
I have seen videos and images of those tunnels as well. One tunnel, that has images of it seems to have broken building pieces as reinforcement and every other I have seen is just been dirt and stone. Nothing like the illustration Israel published, definitely no red barrel room, or even any room, just tunnels.