Sean keeps going forward, his light steady as the tunnel continues into another room.

This place has two other tunnels without doors leading into it. It has a few waist-high concrete barricades and light wooden slat-walls prepared, to break up lines of sight and give cover for anyone holding out here. They are all in front of a single metal security door (locked).

There are no light sources active in the room. Sean checks behind every wooden slat and concrete barrier, but finds no-one hiding here.

It is only by checking the ground and finding a light blood trail, he realizes the person coming through here went into the door.