Found towards the beginning of the level. Just before going inside the underground tunnel, head inside the dilapidated building to the right. At the opposite end of the room, you'll see the first Intel item of the level sitting on the file cabinets to the left.
Enemy Intel Item #26
Heading further down through the underground fortress, you'll eventually pass through a control room filled with computers and multiple monitors. Directly behind the wall of monitors, you'll find the second Intel item sitting on one of the computer desks.
Enemy Intel Item #27
The next Intel item is found on the second floor of holding cells. It'll be in the first open holding cell to the right. Once inside you'll see it sitting on the second desk to the right.
Enemy Intel Item #28
The fourth and final Intel item is found towards the end of the level after your second wall breach in rescuing Prisoner #627. From the in-game cutscene, look over to the left and grab the Intel sitting on the computer desk.
