A COLD case expert has told jurors of a one-in-a-billion DNA match to the alleged Babes in the Woods killer on the arm of one of the victims.

Russell Bishop, 52, is on trial at the Old Bailey charged with the murders of nine-year-olds Karen Hadaway and Nicola Fellows.

The girls were sexually assaulted and strangled in Wild Park in Brighton in October 1986.

Bishop was acquitted of the murders in 1987, but ordered to face a fresh trial in light of new evidence from advances in DNA testing.

Forensic scientist Roy Green tested 14 areas from a taping from Karen's left forearm, taken at the time of her post mortem examination in 1986.

He said the areas were identified as possibly containing skin flakes or other organic material.

On his results, he said: "The result of the DNA-17 analysis showed a mixture of DNA from at least two people.

"The majority of the DNA was an incomplete profile matching that of Russell Bishop.

"Most of the remaining components also contained the DNA of Karen Hadaway.

"There were also three additional components other than from Russell Bishop and Karen Hadaway."

Mr Green looked at two propositions, the first that the DNA was from Karen, Bishop and an unknown person, and secondly that it was from Karen and two unknown people.

He said: "A statistical evaluation of the result was performed, as a result of which it was estimated that the DNA findings would be approximately one billion times more likely if proposition one were true rather than proposition two were true."

Tapings from a blue Pinto sweatshirt found discarded on Bishop's route home were also tested for DNA.

Mr Green told jurors the results found DNA "in excess of one billion times more likely" to belong to the defendant and an unknown person than two unknown people.

Bishop, formerly from Brighton, has denied two charges of murder.