Several planes got too close over Lithuania's southern city of Marijampolė in April, but there was no real threat, Lithuania's state-run enterprise Oro Navigacija (Air Navigation) said on Tuesday following an internal investigation.
"Based on the incident investigation methodology used in the European Union, the mentioned incident is not attributed neither to accidents nor dangerous incidents," it said in a statement.
The investigation showed there was an incident in Lithuania's airspace on April 20 when proper distance was not maintained between two aircraft. After the two planes' Airborne Collision Avoidance System (ACAS) activated, the crews received advisory solutions to avoid collision. One of the crews also received a system alert to avoid collision with a third aircraft.
More serious incidents were avoided thanks to successful system and human decisions, Oro Navigacija said.
The preliminary investigation showed the horizontal distance between the aircraft was no less than 5 kilometers and the vertical distance was no less than 200 meters. The 15min.lt news website reported earlier that the incident possibly took place because of a fatigued air traffic controller.
Two similar incidents were recorded in Lithuania last year, Oro Navigacija's data shows. The state enterprise is now installing a more modern system warning planes about dangerous approximation.
Read More: Lithuanian officials investigate near-collision in April involving 3 planes