The body of a teenage girl was found in a field on the day her parents celebrated their silver wedding anniversary.

Officers arrested an 18-year-old close to the scene on the outskirts of Cramlington, Northumberland, just a few hundred yards from 14-year-old Sarah Robson's home.

Her brothers Ian, 18, and Chris, 20, searched for her on Tuesday night after she failed to return home, said a family friend.

Gareth Savage, 16, a lifelong friend of the brothers, said Sarah's parents, John and Lynn, had celebrated their wedding anniversary earlier that day.

He said: "She was popular around the street, always said hello, and her family are very nice.

"I have known her as long as I have known her brothers and have watched her grow up.

''She was a very nice person, harmless to everyone, and she did not deserve anything like this.

"She will be very badly missed around here."

A tent was placed over the scene where the body was found in a field about half a mile from the A19 and officers sealed off the area of common land.

Detective Chief Inspector Ian Groom said police wanted to build up a picture of Sarah's movements.

She left her parents' semi-detached home in Reedswood Crescent at 3.30pm.

She had been seen with an older teenager on the night she died, but officers were not sure whether she had a boyfriend.

She was seen with a group of youths, two of whom may have been wearing Army cadet uniforms.

Det Chief Insp Groom said the family were distraught. ''This was supposed to be a day of celebration,'' he said. The detective refused to say how Sarah died, but she was fully-clothed when she was found.

A post-mortem examination has been completed but the results are not being released while Northumbria Police continue to question a man about the death.