[Kyiv Post] SEVASTOPOL, Crimea -- Russian forces and Russian-backed Crimean "self-defense" units have moved against Ukrainian army bases in Crimea, following Russian President Vladimir Putin's annexiation of Ukraine's Crimean peninsula on March 18.The Ukrainian navy headquarters in Sevastopol was besieged by Russian soldiers and local self-defense units, assisted by unarmed local people, on the morning of March 19.