Funny looking work train on BNSF... any explanations?

I was in Grand Tower today, to see how low the Mississippi was (it's low!), anyways, I was at Devil's Backbone Park, and if you look right over on the Missouri side, you can get a good view of the BNSF River Sub. Well after a while looking down on the river, I see this work train coming. It consisted of an engine, a flatcar with a crane/backhoe, about 6-7 double-stack flatcars, and another engine. It was yellow with red striping. And mind you, the engines weren't locomotives, they resembled something like a cab-over truck or even the French TGV's. Was it a BNSF owned train, or a contractor?

Like I said, they weren't locomotives, they looked like a cab-over truck with TGV cabs.

According to some BN friends from Chaffee this was a Herzog ditcher.

Thanks Jim, I had no idea what that was until now... And here's a pic of that particular train: http://www.railpictures.net/viewphoto.php?id=108398

I happened to be videotaping today's adventure around Grand Tower when I noticed it, of course I immediately started taping the train, fully zoomed in of course!

Herzog calls it an MPM. Multi purpose machine.
It has interchangable attachments like a bucket, grapple, and magnet.