I did not see it happen, but was there within seconds of when it happened. From what I understand the -9 was under tow with its' nosegear in the cradle on the tug. They rounded a corner doing a fair clip (according to the witnesses I spoke with) and the momentum of the aircraft started to force the tug into an oversteering skid (looks like it was to the tug's right). The tug driver bailed in time so he survived but no one knew the extent of his injuries at that time. (He was taken away in an ambulance.)
So, there were no pax on board but it all happened in full view of at least everyone on the E concourse in MSP.
Could have been a lot worse!! But its a real bummer for NWA.