Bouncer and convicted murderer Levi Bellfield has denied he kidnapped and killed Milly Dowler, the Old Bailey has heard.

The trial of Bellfield, who denies abducting and killing the 13-year-old Walton schoolgirl, began at the Old Bailey this morning.

She went missing while walking along Station Avenue in Walton on March 21, 2002, on her way home from Heathside School, the court heard.

Her unclothed and skeletal remains were discovered by mushroom pickers six months later, 25 miles away in Yateley Heath.

Bellfield also denies attempting to kidnap 11-year-old Rachel Cowles the day before from Shepperton.

Prosecuting Brian Altman QC said Milly vanished in the "blink of an eye" after getting off the train from Weybridge at Walton station to eat chips with friends in the station cafe.

He described her disappearance, which haunted Robert and Sally Dowler, a maths teacher at her daughter's school, as "every parent's worst nightmare".

He said: "On any other school day she would have simply continued her journey home on the train from Weybridge to Hersham station which was closer to her home.

"But on this day an entirely and innocent and quite ordinary diversion to a station cafe with some school friends was a decision that was to cost Milly her life, because it meant taking a fateful journey along Station Avenue where, unbeknown to her, her abductor and killer was soon to strike."

Bellfield and his partner of the time, Emma Mills, their two children and a Staffordshire bull terrier, were living yards away from the station in a ground-floor flat in Collingwood Place, Mr Altman said.

Although they were house-sitting for a friend in West Drayton, near Heathrow, police had evidence Bellfield was there on the day Milly disappeared and also the day before, the court was told.

A red Daewoo Nexia, alleged to belong to Bellfield, was caught on CCTV leaving the flats 22 minutes after she wet missing, the court heard.

Rachel Cowles, 11, was approached by a man resembling Bellfield in a small red car while waking to her home in Hawthorn Way along upper Halliford Road, Shepperton, it was claimed in court.

Mr Altman said he "tried tricking her by telling her that he had just moved in next door and he asked her if she wanted a lift".

"Sensibly, she did not accept his offer. At this time, a police car was driving along the road, which possibly spooked the man, and he drove off," he said.

Ms Cowles, now 20, later failed in an identity parade, to identify the man who attempted to abduct her.

The jury was told of Bellfield's previous convictions, the murder of Amelie de la Grange, the murder of Marsha McDonell and the attempted murder of Kate Sheedy.

Mr Altman said: "There can be no doubt that Levi Bellfield and no one else was responsible for both. He has proven to be a predatory and violent offender towards young women in west London."

The court will visit Walton and Shepperton on Thursday, when the seven male and five female jury members, accompanied by the judge, will see the locations for themselves.

Milly's disappearance was the largest investigation ever carried out by Surrey Police, the court heard.

She would have been 23 next month, had she lived.

Bellfield sat in the dock, with shaven head and wearing a dark suit, white shirt and blue tie.

The trial continues.