Importing multiple fbx animations into one model

So I got some exported fbx animation files from C4D (they were exported as baked animations) and I was looking into merging them into one track in NLA editor in blender 2.79 for a mesh that I wish to convert into an md3 file.

Unfortunately, this isn’t possible with simply importing these files (they will appear as separate meshes). Any method of merging them into one animation track?