NATO member Estonia says an Mi-8 Hip helicopter belonging to the Russian Border Guard intruded into its airspace for about two minutes on Saturday night. ***** Russian warplanes fly through Lithuania’s airspace every week, its MoD said. Like the intrusion into Estonia, they usually have no pre-filed flight plans and transponders that are switched off. Last week there were eight violations, ERR reported and 13 the previous week. ***** Russian naval vessels are also apparently causing problems. The Russian ambassador to Denmark was summoned to the Danish foreign ministry on Friday after a Russian military vessel twice violated that NATO...