The commander of a Crimean air base allegedly surrounded by Russian troops said he will be taken away by Russians for talks.
At least one Ukrainian is reported injured in the standoff at Belbek air base.
An unusually frank Nato Secretary General issued an unequivocal warning on the course of events should Russia attack Latvia or Estonia.
The West responds with sanctions and closer political ties with Ukraine as Russia's President seals the annexing of Crimea to much fanfare.
Supporters of the controversial fracking industry believe shale gas could be America's most potent weapon in the stand-off with Russia.