A large wind turbine worth £500,000 mysteriously collapsed on an Irish mountainside during light winds.

The 262ft tall structure was found buckled and destroyed at Screggagh wind farm on Murley Mountain in County Tyrone, Fintona.

An investigation has now been launched into what caused the huge structure to collapse amid the sound of grinding metal, which could be heard as far away as seven miles.

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The 262ft tall metal wind turbine collapsed at Screggagh wind farm on Murley Mountain in County Tyrone

It remains unclear why the turbine fell on Friday, during a period of light winds which reached around 15mph - the equivalent of a breeze.

The wreckage of the turbine was a mass of twisted and buckled metal.

Debris from the large mechanical structure was scattered across the mountain in northern Ireland, where it stood with eight others.

It is understood the rotor blades spun out of control and the sound of the mechanical structure crashing to the ground was compared to an explosion.

Others said they heard grinding metal and a sound like thunder as the huge structure fell.

Doreen Walker, director of the wind farm, said: 'There were fortunately no injuries and no personnel on site at the time.

Sounds of grinding metal and the large structure collapsing could be heard as far as seven miles away

We are currently investigating the circumstances that led to the collapse of the turbine at Screggagh wind farm.

'We are however satisfied that the site's precautionary health and safety alert processes worked well with local emergency services in attendance within minutes of the incident taking place.

Ms Walker said they were 'working closely' with Nordex UK, the supplier of the wind farm turbines, to ensure the site is safe.

The cause of the fall is being investigated after the turbine bucked during a period of mild winds at the farm site

The turbine fell during a period of light winds on the mountain, in the region of Fintona at Murley Mountain

'A further statement will be made once the investigation has been completed and the reasons for the failure confirmed,' she added.

In January last year a 115ft tall turbine was felled by gales in Bradworthy in Devon.

Months later three turbines - built to withstand winds of up to 115mph fell when speeds barely reached 50mph in Devon.

The Health and Safety Executive found the cause of the crashing turbines was due to faults in the way they had been put together, which could have affected hundreds of others