it looks like night.. so most likely the driver was asleep or falling asleep.. it happens when you overtired, overstressed, overloaded with work, don't sleep properly.. I even know couple of real cases when drivers have fallen asleep and got killed in the bad accidents….that's why i am always worried till my hub comes back home safe, as i know he doesn't sleep enough, works too much...

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“You become responsible forever for what you have tamed”. Antoine de Saint-Exupéry