Right now, it is the company Vestas that has built the wind turbine that is investigating the accident.
They have already concluded that one of the leaves came loose and made the work so unstable that it collapsed.
The Accident Investigation Board also makes the assessment that it is reasonable to trace the accident to a broken attachment between one of the rotor blades and the hub.
They write: "If it is possible to trace the explanation back to a specific defect in the manufacturer's or subcontractor's production process through the manufacturer's investigation, an investigation by the Swedish Accident Investigation Board in this respect would probably not have any more general safety benefits."
The subcontractor who delivered the blades has sold blades to about 185 other wind turbines around the world.
Vestas has recommended all owners to stop the wind turbines while waiting for their investigation to be completed.