Everything has to start somewhere:
A Ukrainian serviceman reportedly was shot and killed and another wounded by masked assailants who stormed a base in Crimea's main city of Simferopol, hours after Russia announced it would annex the Black Sea peninsula.
Ukrainian military spokesman Vladislav Seleznyov tells Reuters by telephone from Crimea that it was unclear who the attackers were. He described them as "unknown forces, fully equipped and their faces covered."
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There is an addendum:
[Add at 5:50 p.m. ET: NPR's Gregory Warner, reporting from Simferopol, says a military source close to the Crimean government said the shooters were likely a "self-defense militia group who were then taken into custody by Russian soldiers."]
Believe what you like.
Maybe this was an isolated incident, maybe it was an escalation of the intimidation of Ukrainian military personnel, maybe it was the first casualty of WWIII.