The Vicky Hamilton trial heard yesterday that the man accused of murdering the schoolgirl told police that a knife with her DNA on it “probably” belonged to him.

Jurors at the High Court in Dundee were shown nearly two hours of videoed police interviews with Peter Tobin, during which he conceded several times that the knife discovered in the loft of his former home was probably his.“Yeah, it's up there. It's mine, you know what I mean,” he said.

Mr Tobin, 62, denies abducting and murdering 15-year-old Vicky and burying her body parts. He has lodged a special defence of alibi, saying that he was in the South of England when she was abducted on February 10, 1991.

Officers were heard on video telling Mr Tobin, who was being interviewed under caution, that a piece of Vicky's flesh had been found on the knife and asking for an explanation. He replied: “Haven't got a clue.”

“Well how do you think it might get on it?” asked Detective Sergeant Alan Goar. Mr Tobin said: “Probably cut herself, or whatever. I don't know.”

The court heard that when the detectives suggested to Mr Tobin that he was responsible for Vicky's disappearance, he said: “No, I'm ... no'. Naw, naw, naw. It's nothing to do with me.”

The trial was told earlier that the probability of DNA found on the knife being that of someone other than Vicky was more than one in a billion.

On large screens in court, jurors saw David Crookston, a former detective constable, point to a picture of Vicky and say: “That lassie - how come a piece of her is in your house?” Mr Tobin replied: “Don't know, can't explain it. Sorry.”

Mr Tobin told the detectives that he reconditioned old cars when he lived in Bathgate. He had heart disease, a bad leg and problems with his back.

The court heard Mr Tobin say on tape that he had few close friends and did not get on with his father.

He said that he had an unexceptional sex life.

The court heard that Mr Tobin's former wife had brought legal action over the custody of their son.

When told by the detectives that his son Daniel's DNA had been found on Vicky's missing purse, recovered from St Andrew Square in Edinburgh 11 days after her disappearance, he said: “How can he? Well, how could he?” Frank Mulholland QC, Solicitor General, prosecuting, asked Mr Crookston: “Did Mr Tobin confirm that if his son was absent from nursery he would be with him?” “Yes, that's correct,” said the detective.

Mr Crookston told the jury that the interviews with Mr Tobin, conducted in July last year, took place before the discovery of Vicky's body from the garden of a house in Margate, Kent, which Mr Tobin used to occupy.

At the close of the taped interview, Mr Tobin was asked to assist the police in finding Vicky for the sake of her family. Mr Tobin said: “Sorry, I cannae help you, know what I mean? As I say, I've never met her.”

Donald Findlay, QC, for the defence, put it to the retired detective that the police shouted at Mr Tobin. Mr Crookston replied: “At times I would say it was assertive.”

The eighteenth day of the trial marked the end of the Crown's case, after hearing evidence from 110 witnesses. The first defence witness was Elizabeth Brown, 51, a nurse who in 1991 recollected having a psychiatric patient called Hugh Gunn who told her that he had “done away with the girl” - referring to Vicky Hamilton.

Further evidence led by the defence came from statements given to the police in 1991 by a woman called Helen Hunter, or Rose, a neighbour of Vicky Hamilton's. She told police that Vicky was drinking alcohol, had tried cannabis and was interested in trying tranquillisers. Vicky had been sexually active, she alleged. Inspector Russell Penman confirmed that, in a second statement, Helen Hunter said that Vicky had brought her temazepan tablets.

The charges against Mr Tobin allege that on February 10, 1991, in Bathgate, West Lothian, he abducted 15-year-old Vicky Hamilton, of Redding, Falkirk, and took her to his home in Robertson Avenue, Bathgate.

There, or elsewhere, Mr Tobin is accused of drugging her, causing an injury to her neck, committing a sexual assault and murdering Vicky.

The charge goes on to allege that Mr Tobin cut the girl in two, wrapped her body parts in bin bags, hid the knives and concealed, transported and buried her remains.

The trial continues.

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