Russian forces used at least two armored vehicles to break into the Ukrainian air base in Belbek after an hours-long tense standoff at the gate. Gunfire and explosions could be heard as the vehicles broke down the gate where Ukrainians had been refusing to allow them entry.
Read more at:
https://www.washingtonpost.com/world/monitors-set-to-deploy-to-ukraine-to-try-to-contain-crisis/2014/03/22/742e4898-b1a4-11e3-a49e-76adc9210f19_story.html