Some of the chaps over on stratpages think that it might be a misident'd commercial contrail, but tbh, to me at least, that looked like a missile. There was no NOTAM released before the launch, and news sources seem to state that NORAD and other traditional ICBM detection services didn't pick anything up, to the extent that they're using the footage released by the news agency to try and investigate it.
All a bit confusing really. I wonder if we'll ever know...