EXPERIENCES learned by Essex Police during its longest and most demanding investigation into the murder and disappearance of Danielle Jones are being passed on to other forces.

EXPERIENCES learned by Essex Police during its longest and most demanding investigation into the murder and disappearance of Danielle Jones are being passed on to other forces.

Essex Police has produced an interactive DVD covering Operation Spinnaker, its investigation into death of Danielle Jones, 15, from East Tilbury.

The operation cost the force £1.7 million and involved almost 1,000 officers and support staff.

Her uncle, Maldon-born Stuart Campbell, 44, was convicted of her murder in December last year and sentenced to life.

He has given notice of appeal against his conviction, and has refused to tell detectives where her body is.

A police spokesman said the aim of the DVD was to help other forces learn from the experience in Essex should they have to carry out a similar investigation.

It includes sections on how police resources are used and responses to public appeals. An appeal on BBC programme Crimewatch UK resulted in 830 reported sightings of the teenager but all proved false, said the spokesman.

Det Chief Supt Steve Reynolds said it prompted thoughts about the demands faced by a senior investigating officer who becomes "completely consumed by the demands of the media" at the same time as running the investigation.

He said: "I think we expect too much of senior investigating officers (SIO) to think that they can lead investigations and service the demands of the media.

"An SIO needs to lead the team so there is the question of whether there are sufficient hours in the day to be on top of dealing with the media."