Harsh Blue Lighting Artifacts

Hey guys,

I've been working on a scene and it's all been alright until all of a sudden after a light bake these strange, harsh, blue errors started popping up in the areas of the scene that a mostly in shadow. Any help would be amazing as I've got a hand in for this scene in the next couple of days!

Thanks!


Note: I've brightened the image so it's easier to see