The ex-bouncer accused of stalking girls near bus stops admitted he was at the scene of one of the attacks, but claimed that a friend was responsible, a court heard.

Levi Bellfield, who took the stand this week for the first time, told the Old Bailey that as he drove past a bus stop in Longford he saw his friend Sunil Gharu "pulling" at a girl, Kosovan born Irma Dragoshi.

Bellfield, 39, told the jury: "Part of me was in shock. I did not know whether he knew her or if it was ongoing. I did not want to get involved.

"He was not punching her. If he was attacking her I would have got out of course."

Bellfield denies her attempted murder, that of Kate Sheedy, the murders of French student Amelie Delagrange and Marsha McDonnell and the abduction of Anna-Maria Rennie.

The court had heard earlier in the trial that Mrs Dragoshi suffered a lump on her head bigger than her hand, which may have been caused by blow from a blunt object.

Bellfield said he had driven to Longford on December 16, 2003, with fellow wheel clamper Mr Gharu and another colleague, whom he could not remember.

He said he witnessed the incident after leaving the pair so he could look at a property at 7.30.

He claimed he drove from the scene before the pair got in the car, when Mr Gharu told him that his girlfriend's phone had been stolen and he believed the girl at the bus stop was involved.

Describing the state of Mr Gharu, Bellfield said: "He approached panicking, he ripped the back door open and slid in. He seemed really out of breath."

Bellfield had earlier told the court he was watching the Michael Jackson television interview with Martin Bashir on the night gap year student Marsha McDonnell was murdered. He said he was "pretty certain" that at the time Miss McDonnell was killed he was at home in West Drayton with his girlfriend Emma Mills and their children.

He said he remembered the programme, which was aired on February 3, 2003. Jurors heard earlier that Miss McDonnell was killed by three blows to the head with a blunt object at just after midnight after getting off a bus in Hampton. Asked by defence counsel William Boyce why on February 8 he booked to go on a last-minute holiday with his family the following week, Bellfield replied: "The business was doing fantastic."

On the day of the attack on Amelie Delagrange on Twickenham Green on August 19, 2004 Bellfield said he was shopping with his children in Toys R Us, before going to a pub in Harmondsworth, West Drayton at around 10pm, then on to his girlfriend's house by taxi.

When asked to account for his movements on the night of Anna-Maria Rennie abduction in Whitton, October 15, 2001, Bellfield said: "The day is my son's birthday.

"I believe and I say this, I believe, that I was having a Chinese out that night."

Mr Boyce asked him if at that time he owned or had use of a blue or green Mondeo, with part of the registration reading L651, as described by Miss Rennie, Bellfield replied: "No I did not."

Bellfield confirmed to the jury he has a number of previous convictions, which date back to 1982. They range from drunk and disorderly to ABH on a police officer in 1991 over a row about loud music, for which he was imprisoned for six months.

The trial continues.