Natalie McClelland took this photo of a grey stripe in the sky over Cockermouth on Sunday.
She said: "I thought it was really odd as it was perfectly straight and showed no signs of dissipating as we watched it like contrails do.
"It seemed to sit over the clouds which another reason I thought it was odd.
"Does anyone know what it is? Or know of any event that it could be linked to?"
Tell us below.....
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