The Estonian military says Russian aircraft violated Estonian airspace over the Baltic Sea, the fourth such violation by Russia this year.
The military said in a statement on September 6 that a Russian Antonov An-72 transport plane was in Estonian airspace without permission for about 90 seconds near the Baltic Sea's Vaindloo Island.
It said the Russian plane was not in contact with Estonian air-traffic controllers and had flown some 2.2 kilometers inside Estonian airspace.
Russian Defense Ministry spokesman Major General Igor Konashenkov told journalists on September 6 that no Russian planes "violated Estonia's airspace in the vicinity of Vaindloo Island."
He claimed that no Russian An-72s flew on September 6 in the area cited by Estonian officials.
The Russian Embassy in Estonia said its ambassador had been handed a protest note by Tallinn officials.
Several NATO countries have reported airspace violations by Russian aircraft this year.
Turkey shot down a Russian warplane late last year that it said was violating its airspace, something Turkish military officials said had happened several times and that Moscow had been warned about.
Based on reporting by dpa and TASS