Huge white UFO spotted over a road in Michigan

On June 2, 2016, an automobilist was driving on a road near Hamtramck (Michigan) when he has seen, in the sky, a big white bright UFO. What is it?

Witness statement:

I was on I-75 near Hamtramck driving it didn't look normal it was bright in the sky is thought it was a bird it hovered and went west to east moving back and forth over the freeway it kept moving back and forth in a straight line freaked out confused and then started taking pics I turn around to talk to someone and lost sight of the object.