A foreign military aircraft almost collided with a passenger plane that had taken off from Copenhagen, according to reports.
Swedish authorities are investigating after Swedish Air Force chief, Maj Gen Micael Byden, said that the military aircraft's transponders, which make the plane visible to commercial radar, were shut off.
According to the Daily Telegraph, upon discovery of a foreign plane over Östersjön, both the Swedish and Danish armed forces dispatched combat planes to identify it.
According to thelocal.se, the fighter jet was from Russia. Defence Minister Peter Hultqvist told the TT news agency: "It's about a Russian military jet. We have identified it via Swedish combat pilots. There are no doubts about what kind of government aircraft it was."
He added: "This is serious. It's inappropriate. It's downright dangerous."
The Star reports that Byden said the Friday's incident in international air space looked "pretty serious".
The paper adds that the southern-bound commercial flight was immediately ordered to change course.
Daniel Josefsson, who works in combat management at the combat control centre in Luleå, said: "Suddenly the military plane took a sharp turn and the way I understood it is that there was about a minute from being a collision course with a passenger plane."
Byden added, however, that it was not as serious as an incident in March, when a Russian plane flying without transponders came within 300ft of an SAS plane taking off from Copengagen.
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