It was in colour, dubbed in Russian (I have a feeling the original language was English but not 100%) and seems like 10 years ago at least was when I’ve caught it.

The scene there goes as follows: two guys are trying to take cover in some open outdoor area. Then the scene changes and a guy with a scoped rifle appears on the high ground, he spots the pair taking cover, reports to someone on the radio that those in cover are not real soldiers but are just masquerading as ones. Then he proceeded to shoot both of them. The fourth older guy apparently connected to those recently shot sees all this, tries to get in the truck and drive away but is also shot and killed.