Aviation safety risks increased significantly last year as "non-co-operative military aircraft" crossed paths with civilian planes over the Baltic Sea and other waters, European air safety officials said in a report published Tuesday.
A European source told AFP that the unidentified military jets mentioned in the report by the European Aviation Safety Agency (EASA) were essentially Russian warplanes that have increased activity since the Ukraine crisis erupted last year. The European Commission last year tasked EASA to investigate a series of near-misses with Russian military aircraft not using the transponders which identify them and tell other planes of their position.
"The number of safety occurences involving civil and non-co-operative military aircraft over the high seas, in particular over the Baltic Sea, has significantly increased in 2014, compared with past years," EASA said in its report.
It said that over the Baltic Sea, 16 incidents involving "non-co-operative" military jets occurred in 2014, including three that violated the airspace of European countries and 13 where they flew dangerously close to a civilian airliner.
This marked a four-fold increase in risks over 2013, it added.
"In two cases, the pilot and ATC (Air Traffic Control) reports indicated that if no avoiding action had been taken, the chance of collision would have been very high," it said.
In the most dangerous case described by EASA, two planes flew only 100 metres (300 feet) apart vertically and 0.5 nautical miles (900 metres) apart horizontally.
It did not list the date or the location of the incident.
In the first two months of 2015, EASA recorded three intrusions by military planes in the air space of the Baltic countries. EASA said they were military aircraft which did not transmit their flight plan to aviation authorities, did not communicate with air traffic control and had cut their transponders.
"We are basically talking about Russian military aircraft here," a European source told AFP on condition of anonymity when asked to identify the origin of the military planes mentioned in the report.
EASA didn't identify the nationality of the military planes.
On December 12 last year, Sweden said that a Russian military jet nearly collided with a passenger plane south of Malmoe shortly after take-off from Copenhagen International Airport.
Both countries called in their Russian ambassadors to protest, only to be told that a huge increase in Russian military activity in recent months was "a response to NATO's activities and escalation in the region."