I'd like to see a full-frame photograph before judging anything. Pictures that are blown up and cropped to the point where the dust on the camera lens becomes a prominent feature of the image never impress me much.
That said, it could be anything. The things it most looks like to me are things that you wouldn't see in the sky, though: poor exposure or development or light leakage if it's a film photograph, a laser pointer or similar bright light source if it's a digital photograph.
Unless we hear stories coming in from more people, I'm inclined to say this witness's testimony is likely to be rather more fanciful than the truth. What she describes is spectacular, anyone else who was looking at the sky at the time would have to have seen something like that. Google says Moss is a town of ~40,000 people, so I have a hard time believing these were the only people in the area to look up during this 5-minute period.
