The Ecotricity turbine, in Conisholme, Lincolnshire, had one 66ft blade ripped off and another badly mangled following a mystery incident on January 4.

The company recovered the blade and has sent it for forensic testing in a bid to determine what happened to the turbine, which is one of 20 that have been operating at the site since April 2008.

But locals, UFO spotters and the tabloid press have developed their own theories to explain the damage.

One local resident, Dorothy Willows, told The Sun newspaper that she was in her car when she saw “strange lights” in the sky.

“The lights were moving across the sky towards the wind farm,” she said. “Then I saw a low-flying object. It was skimming across the sky towards the turbines.”

Since the incident, other apparent sightings of UFOs around the same date have emerged, and are being linked to the turbine damage.

Enthusiasts on have questioned whether a video showing a hovering light in the sky near Scotland’s “UFO hotspot” Bonnybridge is the “turbine UFO”.

Ecotricity said it was still investigating what had happened, and denied that the wind turbines posed any risk to public safety.

In a statement, the company said: “We’ve examined the turbine, the fallen blade and the surrounding area, looking for clues.

“We also sent parts of the fallen blade away for more forensic testing.

“We have been liaising with the Health & Safety Executive and the local council. Both are satisfied that this is a unique and isolated incident.

“We, and they, have no concerns with the ongoing safety of this, or any of our other wind parks.”

The Ministry of Defence has said it is not looking into the incident.

Kate Martin

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