A forensic scientist was "pinned against a wall" by a senior police officer after he gave evidence in the first Babes in the Wood murders trial, a court heard.

Dr Anthony Peabody told jurors that "emotions ran high" before Russell Bishop's 1987 acquittal for killing nine-year-olds Nicola Fellows and Karen Hadaway.

The retired scientist was called to give evidence again after a fresh trial was ordered in light of new evidence following advances in DNA testing.

Dr Peabody, who worked at the Aldermaston laboratory, recalled how he went to the scene in Wild Park, Brighton, after the girls were found dead in a woodland den in October 1986.

He told jurors: "The area was deep in undergrowth - ivy, brambles, elder and other vegetation.

"The area where the bodies were found may best be described as a den. It was a hollowed-out area within undergrowth. Branches formed a roof and ivy was abundant in the den at its entrance and on the approaches to it."

Dr Peabody was quizzed about the examination of the children's clothes and a blue Pinto sweatshirt allegedly discarded by Bishop as he walked home on the night of the killings.

Fibres taken from the clothes led Dr Peabody to conclude the Pinto sweatshirt may have been in contact with the defendant's trousers and clothes belonging to his then-girlfriend and the dead girls, jurors heard.

Explaining his results in 1987, Dr Peabody said: "My findings provided strong evidence to indicate the (Pinto) sweatshirt had been in contact with the clothing of the two dead girls."

He said ivy hairs on the sweatshirt and girls' garments suggested "sustained contact with ivy" and not from "merely walking through undergrowth where ivy is present".

Prosecutor Alison Morgan asked how seriously the scientist took the dangers of cross-contamination at the time.

He replied: "Cross-contamination was something we took every step that we could to minimise if we could possibly do so. We were very conscious of cross-contamination."

Items arrived at the lab in sealed bags and were examined in different rooms which would be swabbed down afterwards, he said.

Cross-examining, Joel Bennathan QC said: "As you left the witness box in 1987 you were pinned against a wall by the senior police officer."

Dr Peabody replied: "As it happens, yes."

Mr Bennathan went on: "I don't want to go into the rights and wrongs of that but he was unhappy about the way the evidence came out?"

The witness said that "emotions ran high" at the time.

Mr Bennathan suggested Dr Peabody used sticky tape when taking fibre samples, knowing the roll might be contaminated.

The scientist insisted he observed good scientific practice and did not use tape "willy-nilly", adding he was "shocked" at the suggestion.

The lawyer asked Dr Peabody why he had not followed up on a white fibre taken from the Pinto sweatshirt similar in appearance to the material from a police suit.

He said: "Are you not interested in possible signs of contamination? You should be shouldn't you because even if something comes to you properly sealed, if you found something that might suggest contamination before it gets to you it would be proper to make a note of that and explore it.

"You knew the Pinto was found before the girls were found."

The witness insisted that it was not certain the white fibre was from a police suit and he did not feel the need for further examination.

Convicted sex predator Bishop, 52, formerly from Brighton, denies two counts of murder.