Denmark halted traffic in a busy shipping lane and closed the airspace above it on Thursday, warning of a possible accidental missile launch and falling debris.
During a test of a Harpoon anti-ship missile, its booster — the rocket engine that launches the missile — was “activated” but not ignited, and then it could not be deactivated, the Danish military said.
“Until the booster is disabled, there is a risk that the missile could launch and fly several kilometers,” it said in a statement.
Denmark’s Maritime Authority warned that there was a risk of missile fragments falling near the shipping lane, known as the Great Belt.
The military said that only the booster was activated, not the engine that takes over after launch, and not the warhead, so the missile could not travel far and the warhead could not detonate.
The mishap came just a day after the Danish government fired its chief of defense, the highest-ranking uniformed military officer, Gen. Flemming Lentfer, after a report of weapons systems failing on a ship that was taking part in the U.S.-led effort to guard shipping near the coast of Yemen.
The missile test on Thursday was conducted aboard a frigate, the Niels Juel, in the port of Korsør, which sits beside the Great Belt.
The Great Belt is the strait between Denmark’s two largest islands, Zealand and Funen, and is part of the main shipping route between the North Sea and the Baltic Sea. Annually, tens of thousands of vessels of all sizes and types pass through it, transporting cargo and people, according to DanPilot, the country’s pilot service. The strait has dense traffic and strong currents.
“From those I have spoken to in the Navy, they are taking it very calmly,” said Søren Nørby, an assistant professor at the Norwegian Defense Academy. “They are not evacuating Korsør town or anything. If it goes off, there is about 52 kilograms of metal object flying and falling down.”
It might do some damage, he said, “but there’s nothing about to explode.”