"Up until now, in most of these cases we haven't been observing a situation that would be clearly hostile against NATO," the Czech general said in a public talk organized by Politico.

"There are some violations of airspace, not necessarily incursion into NATO territory, but we are mostly witnessing what we call unprofessional behavior in the air," Pavel clarified.

Such incidents have been recorded not only above the Baltic Sea, but also above the Black Sea and close to the Syrian borders, the general added.

"There is always risk that something will go wrong when two forces that are not friendly are too close to each other," Pavel said, noting that NATO is trying to develop mechanisms with Russia which would enable them to discuss transparency and risk reduction measures to avoid even potential incidents.