"The Russian Federation sent a fighter jet to check the situation, and this fighter jet violated NATO territory for close to one minute," Estonian Foreign Minister Margus Tsahkna told reporters.
The officers with Russia's FSB concluded no sonic devices were used to violently disperse a March 15 mass demonstration in Belgrade, Serbian President Aleksandar Vucic said.
Estonian transport authorities said Saturday they won't allow the Kiwala oil tanker to pursue its journey until it has resolved 40 legal and safety issues.