Detectives hunting the killer of Sarah Payne have discovered photographs of the abduction scene which could prove to be the "crucial clue" they have been looking for.

A plane taking aerial photographs as part of a routine Government environmental study captured vehicles using the country roads close to where eight-year-old Sarah was playing in the hour before she was snatched, police said.

Officers working on the inquiry are now enlarging and enhancing the high-quality images in the hope of identifying the killer.

It is believed the killer may have abducted Sarah in a white Transit-style van close to her grandparents home in Kingston Gorse, near Littlehampton, West Sussex, on July 1. If the vehicle is on the film, officers may be able to identify it and track down its owner.

A Sussex Police spokesman said: "We are now trying to enlarge the photographs to look at vehicles using the coast road. The film may possibly be a very vital piece of information."

The plane was flying over the area taking photos for the Environment Agency as part of a study of coastal erosion between Littlehampton and Bognor.

It passed over the roads around Sarah's grandparents' seaside house shortly after 6pm on July 1. Sarah left her two brothers and sister playing in a cornfield between 7pm and 8pm.

Detectives working on Operation Maple hope the killer may have been caught on camera cruising the area, or lying in wait for Sarah.