Forensic experts today continued to examine the properties of Canynge Road where both architect Jo Yeates and the landlord arrested on suspicion of her murder lived.
One of Britain’s high profile, Government-funded forensic laboratories working for the nation’s policed forces, shed light on the various processes being used by CSI investigators at the scene.
The entrance to 44 Canynge Road yesterday carried a police sign warning that dangerous chemicals were in use.
Experts revealed that this, and the use of specialist lasers, is common practice for forensic teams in the hunt for minute fingerprint traces or area which have been hyper-cleaned.
CSI officers often use a chemical known as Ninhydrin when testing for fingerprints.
Ninhydrin is used in liquid form when applied to porous surfaces such as wallpaper and used as a powder on wooden floors.
Officers have, in recent days, also used lasers in the same properties.
The Forensic Science Service yesterday revealed that lasers are used to ”show evidence of a clean up”, possibly pointing out whiter areas that may have been specifically cleaned.
Another vital part of forensic science is the study of fibres which are found on textiles in properties, cars and clothes.
Ray Palmer, principal forensic scientist at Forensic Science Service Ltd, said: ”Fibres are particularly important for investigations when the body is deposited away from the murder place.
”They will often give an indication of whether two people were in contact and how recently.”
The fibres examined in many cases are made up of the components of a thread – quite often invisible to the naked eye and unique to one person.
Mr Palmer, who worked on the recent Suffolk Strangler and Jigsaw cases, added: ”When extracting fibres, scientists will sometimes use forceps but in most cases use a tape which can seal or preserve fibres before returning them to the lab to be examined.
”At the lab they will be put under a low-power microscope, which allows us to remove the fibres and then examine them under a high-power microscope.
”It’s a form of reverse engineering and can provide intelligence to the police.”
The FSS are not involved in the current investigation.