Some residents of Conisholme, England, reported lights in the sky and a loud noise at about 4 a.m. Sunday and the turbine was discovered later in the morning with one of its blades ripped off and another blade twisted, The Daily Mail reported Thursday.
The company that operates the wind farm, Ecotricity, said the cause of the damage to the turbine has not been determined and an investigation is under way.
Robert Palmer, 66, head of the East Lindsey District Council and member of the Lincolnshire County Council, reported seeing a bright white light with orange borders while he was driving near the turbine early Sunday morning.
"I would be very interested to find out what it was," Palmer said. "If we are being looked at by other people, by other planets, it would be interesting to find out why they have chosen this part of the country."
Fraser McLachlan, chief executive of wind turbine insurer GCube, said wind turbines break for reasons that are not immediately apparent about five or six times a year.
"It does happen that a blade will sometimes just come off a machine for one reason or another," he said. "The main reason is the blade may shear."
"We don't normally see things like aircraft -- or UFOs -- hitting them. It's usually a mechanical failure that causes the blade to separate from the main hub," he said.