Safety concerns have been raised after a turbine blade at Scotland's most powerful wind farm shattered.
The incident left one of the turbine blades shattered
Details of last week's incident at Crystal Rig, in the Lammermuir Hills near Dunbar, have only just emerged.
A spokesman for the wind farm said that an investigation was under way and there were no conclusions yet.
The research group, Scottish Wind Assessment Project (Swap), said it highlighted safety implications of blades becoming detached at high speed.
Swap said the incident raised real questions about the possible siting of turbines near houses and public roads.
Spokesman said David Bruce the blade "literally flew apart" in recent high winds.
The 2.5MW turbines were installed in August 2004 and can produce power for 33,000 homes.
They are operated on behalf of Fred Olsen Renewables and Natural Power Consultants Ltd.
A member of the public who observed the turbines said: "In the gales I noticed that all bar one were motionless. The remaining one was going berserk."
Mr Bruce said: "This is not something that happens every day but these blades weigh several tonnes.
"If you were the person who was underneath it when it happened you wouldn't care less how rare it was."