THE red Manchester United shirts worn by Holly Wells and Jessica Chapman in their last photograph could prove crucial in convicting the girls' killer, the prosecution claimed yesterday.

Scientific evidence links Ian Huntley and his house with the shirts, primarily through microscopic fibres, the jury was told.

The assertions emerged on the third and final day of the opening speech by Richard Latham QC, the prosecutor, in which he outlined other forensic evidence from Soham and Lakenheath, where the girls' bodies were found in a remote country ditch.

He said the shirts had been cut almost exactly in half as they were removed from the girls' bodies. Photographs of the shirts showed how they were cut vertically from the bottom hem to the neck, almost exactly along the centre of the tops. Similar cuts were made up the back of the shirts.

Chemical tests were conducted to see if there was any link between the fibre and dye used in the shirts and Mr Huntley. ''The scientists found that fibres from Mr Huntley's clothing and carpets and other items in the house matched precisely the fibre from which the Manchester United shirts were made.''

Mr Latham told the court the shirts were likely to shed short fibres when they were cut. Short fibres were far less likely to be spotted by the naked eye and picked up, and more likely to survive the washing process. ''We suggest that the most likely recipient of the fibres would be the cutter.'' Mr Huntley got fibres from the girls' red shirts on himself, Mr Latham alleged .

He said 15 fibres were found on a yellow shirt discovered in the main bedroom, three on a pair of beige trousers, again in the bedroom, and one on a grey fleece, also in the bedroom. They came, he alleged, from one or other of the shirts or both.

The jury was given a list detailing the number of fibres attached to other items, including Mr Huntley's car boot carpet, and furniture, and carpets from various rooms in his house.

He said the new car boot carpet came from the house, and was an offcut from the bedroom.

''You may think the purpose of replacing the boot carpet is to put a piece in the boot to replace the fitted carpet on the night when the car was used to take the bodies away,'' said Mr Latham.

Twelve carpet fibres discovered on Jessica's shirt could ''either have come from the carpet in the boot or the carpet in the house. That may be significant, if you think about it,'' he said. ''That is a two-way transfer. Now we get items found in the house or car going the other way - back on to her shirt.''

In total, 39 fibres from Mr Huntley's clothes were found on Jessica's shirt and 38 from his clothes, house, or car found on Holly's shirt.

The jury was shown photographs of the piece of carpet in the boot and the prosecutor drew their attention to other items in the picture, including a red petrol can and a large pair of scissors.

Mr Latham claimed that seat covers and a throw, previously seen over the Ford Fiesta's back seat and shelf, had been removed from the car after the night the girls vanished.

Turning to the scene at Lakenheath, he said it was plain the clothing was cut from the bodies after they were in the ditch.

One of the scientists who examined the scene was Patricia Wiltshire. As well as examining the primary area down to the bodies, Ms Wiltshire identified what she believed was a second route into the ditch through nettle beds.

Mr Latham explained that nettles when crushed do not die but begin to regrow. Although her findings could not be a precise science, he said her conclusions were that the nettle regrowth period was approximately 13.5 days. Mr Latham said: ''The children went missing on August 4 and their dead bodies were found on the 17th.''

James Howarth, a fire expert, examined the scene and estimated fire damage approximately two metres from the bodies and up to a height of three metres above them. Mr Latham said Mr Howarth suggested the pattern was in line with the use of a liquid accelerant, adding: ''Petrol would be an obvious example, would it not?''

He asked the jury to remember the first Wednesday night after the girls were killed and Mr Huntley's growing concerns about DNA, the red petrol can in his boot, and his visit to his grandmother, Lily Gollings, who lived nearby in Lakenheath.

Geologists concluded that samples from inside and outside the Fiesta matched the ''very unusual'' chalk on the track near the ditch. ''Deposits found in the driver's footwell suggest he stepped on the track and jumped back into the Fiesta, depositing chalk in the footwell.''

Ms Wiltshire had also taken samples from the pollen grain of plants around the site. In all, she found 64 species, some of them quite rare, which were then compared with pollen grains found on the pedals, footwells, and petrol can in Mr Huntley's Fiesta, and on two pairs of his shoes. Several matches were found, Mr Latham said.

Mr Latham said the jury would appreciate the significance of the matches. ''Mr Huntley had possession of a red petrol can on Wednesday and that petrol can can be linked by the evidence to the site. The Fiesta can be linked to the track. Mr Huntley can be linked to the site. It is his car, they are his shoes, the red petrol can is in the boot, the scissors.''

He explained that there was an extensive search of Mr Huntley's house, including the furnishings, floorboards, carpets, kitchen units, plasterboard, bathroom fittings, door and window frames to see if there was anything which could show the presence of the two girls. ''Not a single head hair or fingerprint of either girl was found, that is to say apart from Holly's prints on the chocolate box given to Maxine Carr as she left the school.''

Mr Latham said the jury may believe that ''absence itself'' may be seen as highly significant, and the fact there were no fingerprints supported what the Crown suggest was ''an exceptionally detailed clean-up in order to try and remove evidence''.