An investigation is under way after a research rocket fired from Sweden malfunctioned and ended up landing in Norway.
The Norwegian foreign ministry has said its authorities take “any unauthorised activity” on its side of the border “very seriously”, according to reports.
The rocket, which looked into weightlessness, had reached orbit at a height of 250km (155 miles), where experiments were carried out in zero gravity before it went off course.
It took a slightly longer and more westerly trajectory than calculated, said Sweden Space Corporation (SSC) – which was behind the launch.
The rocket and its payload came down at an altitude of 1km in a mountainous area 15km (9.3 miles) inside Norway. This was about 40km northwest of the planned landing site.
It landed in an area where nobody lives, and was “10km from the closest settlement”, said Philip Ohlsson from SSC.
The projectile, which blasted off from Esrange Space Centre near Kiruna in northern Sweden on Monday at 7.20am local time (8.20am UK time), was supposed to land in an area close to the border.
Work is taking place to recover the payload and an inquiry will establish the technical reasons behind the unplanned flight path, said SSC.
Mr Ohlsson said procedures were in place for when such things go wrong. The company then informs both the Swedish and Norwegian governments and others.
The head of Esrange Space Centre, Lennart Poromaa, told Norwegian news website NRK that Norway’s defence officials had been given prior notice the launch was happening and were updated when the rocket landed in the country.
The Norwegian armed forces’ operational headquarters confirmed they received these two notifications from the Swedes, NRK also reported.