Strange green staining on a couple of objects


Got a strange problem that’s suddenly happened and I can’t seem to get rid of. I seem to have a weird green staining on some objects that’s appeared out of nowhere.

I’ve been through the lights in my scene and I don’t have any green lights, so I’m at a loss as to where it is coming from and how to get rid of it.

The house in the attached image is built up 3 objects - front of house, side of house (both made in 3DS max) and cube (the corner) (cube is made in UE4). You can also see it is staining part of the ground as well.
Anyone know what might be causing this?