linkSecurity guards have been sent to protect the wind farm site in Conisholme, Lincs, following last week's incident.
One of the turbine's 65-foot blades came off and another was damaged at the site, on the same night that local residents reported seeing orange-yellow spheres in the sky, which some described as trailing octopus-like "tentacles".
Ecotricity, the company that owns the wind farm near Louth, has yet to find an explanation for the damage.
But managers are believed to be concerned UFO enthusiasts will scour the site for debris, so have decided to restrict access.
Dog patrols have been sent to ensure no unauthorised people can enter the site.
Nick Pope, a UFO expert, told The Sun: "There may be something they don't
Even the aliens are fed up with global warming. :D