Ukraine crisis: Pro-Russian crowds confront troops
15 April 2014 Last updated at 23:33 BST
Government forces have begun trying to take back the buildings occupied by pro-Russian activists in about a dozen towns in eastern Ukraine.
Gunfire was heard at the airbase at Kramatorsk, which Ukraine's acting president says has been "liberated" from "terrorists".
However, troops sent to reclaim the base faced a crowd of angry locals. Gabriel Gatehouse reports from there for BBC Newsnight.