Russian president Vladimir Putin says that - in case of the full-blown invasion of Ukraine, Russian military forces will be using terrorist tactics. See the video (translation below):
https://www.youtube.com/watch?v=ouIsFUqAJiU - this video has been removed
Translation: "We do not intend to fight with Ukrainian people. I want you to understand me clearly. If we make such a decision [to start the invasion], that will only be for the protection of Ukrainian citizens. And let us see if anyone from the [Ukrainian] military shoots at their own people; we will be standing right behind them. Not in front, but behind them. Let them try shooting at women and children".
To remind the readers, Putin invited the Hamas organisation for the talks in Moscow in 2006. Hamas is considered a terrorist organisation by the European Union, USA, Australia, Canada, Israel and Japan. The tactics employed by Hamas include "the deliberate use of civilian homes to hide and/or protect Hamas arms and munition depots and manufacturing sites", and "the unscrupulous use of civilians as human shields against anticipated air-strikes".
Source: Anton Shekhovtsov's blog