Rig - Mesh is imported as bones! Why?

Hi,

Iam using Maya to rig a mech. When rigging in maya, I create groups in outliner to organize my bones, meshes, and constraints. But when I import it to unreal, it creates additional bones in the origin (0,0,0) that doesn’t exists in the rig inside maya!

I moved the bones to the same group of meshes in the example below, same issue. Can anyone provide some light here ?