Eighteen-year-old Allhana Harris, from Shilbottle, had been out snapping shots for her portfolio at Morwick Mill, next to the River Coquet near Warkworth.

Her boyfriend Martin King, also 18 and a motor mechanic, also took some photographs with her modern, professional-standard digital camera.

But when they later viewed their work, they were stunned to find glowing white 'sparks' on all of Allhana's pictures.

Some appear to have trails of light, suggesting they are moving quickly.

Even stranger, nothing similar appeared on any of Martin's shots, which were interspersed with his girlfriend's.

"We were really surprised to see all these objects on my pictures," said Allhana, from Fallodon Avenue.

"The camera was working fine, the weather was overcast but fair, and the lens was clean. At first I thought it might have been water droplets, but the more I look at the pictures the stranger they seem."

Paranormal investigators have long been investigating so-called 'orbs' which mysteriously appear on photographs and even film.

While they suggest the phenomenon could be linked to supernatural activity, skeptics dismiss orbs as mere lens reflections or dust particles captured by the sensors used by digital cameras.

Allhana added: "We can't understand why nothing showed up on any of Martin's pictures. You would think that if this was something normal it would have appeared on all the photographs.

"He's quite skeptical about the paranormal, but this has rattled him a bit."