A microscopic speck of blood has solved a seven year mystery surrounding the brutal murder of a young woman.

Julie Smailes, 27, was strangled and stabbed 45 times in a frenzied attack in the bedroom of her County Durham home in 1996.

Police suspected John Thompson, 27, of the killing but were never able to find the evidence to pin it on him.

Two years after the killing, Thompson was found hanging from a tree soon after the sickening hammer murder of 18-year-old trainee teacher Rachel Tough.

The coroner at his inquest said there was no doubt he had murdered Rachel before taking his own life.

Now he has also been blamed for the murder of Julie, a manager with a communications firm, after a technological breakthrough.

Police discovered a tiny dot of blood on Julie's bed which did not belong to her and cutting edge DNA techniques have been able to identify as Thompson's.

The tiny speck of Thompson's blood was found on a pillow case already soaked by Julie's blood.

Advances in DNA technology have recently enabled forensic scientists to say that it is a billion to one chance that it did not belong to Thompson.

Detective Superintendent Harry Stephenson, leading the enquiry, said: "The blood on the pillow case was examined from day one but until recently there was not the forensic knowledge available to say it was not just the blood of Julie.

"New DNA analysis techniques became available last year and these were conducted by scientists using the most up to date technology at the police forensic science centre in Wetherby.

"Scientists said Julie was bleeding but it has now become apparent John Thompson was bleeding too.

"The tests were able to establish for the first time that an absolutely tiny, microscopic, speck of blood on that pillow case belonged to Thompson but that was enough to identify him and put him at the scene of the murder.

"In addition to the pillow case there was a point of exit from Julie's house, a tiny spatter of blood on the patio door, which also belonged to Thompson.

"He was a suspect for us from the very beginning but was very strongly alibied.

"On the morning after Julie's body was found Thompson travelled to London and while there got a parking ticket to prove that fact.

"If John Thompson was alive today I would be arresting him on suspicion of murder.

"I have discussed the latest devlopments with the CPS who believe he would have stood trial and perhaps been convicted of murder.

"We also believe there were another three people involved in Julie's death, we have a number of documents giving us information and intelligence of the people involved and we are well aware of what took place that tragic day.

"It is those people who I would like to help me convert this into proper evidence and we will be able to go on and make further arrests.

"The same three names of men from the Consett area have been given to our investigating team time and time again over the past seven years.

"I cannot describe how frustrating it has been to hear these names over and over again yet never be able to convince people to make formal statements and not be prepared to stand up in court and tell us what they know.

"Whether it is through fear of any repercussions we do no know but as today's new evidence has revealed we are not far from getting concrete evidence which will bring these other three men to justice."

Julie's mother Joy Gilmour, 56, travelled from her new home in County Donegal to make a further plea for anyone with information about her daughter's death to come forward.

She said: "The names of these three other men have been known to me for a number of years and although I do not know them personally my friends and family in the North East know who they are.

"As a mother it is heartbreaking to know that we still cannot bring these people to justice.

"God gave us all a conscience and I would ask people to please do the right thing and come forward."

Remarkably Joy said she felt compassion for Thompson. She said: "I did not know the boy but I know that when I heard he had hung hmself after the second murder that I could feel despite my anger and hurt and mixed emotions about it I had a small compassion for him.

"For a man to be in such a frame of mind to kill himself tells me he felt some pain.

"But justice was denied when he took his own life."

She said that Julie and John Thompson were not close associates but she added: "I know Julie had been a teenage friend of Thompson's wife Michelle and I know she knew her through ski holidays at school, but that is the extent of the connection as far as I know.

"This news is bitter sweet. I moved to Ireland because I thought it would mean closure an losing Julie and I was looking forward without having to deal with this case any more."

The horrific violence of Julie's murder shocked the small town of Consett on October 30, 1996.

Her house was then set ablaze and firefighters found Julie's body when they were called out by a neighbour in the early hours.

The murder was featured on BBC TV's Crimewatch programme and during the course of the investigation police questioned 7,000 people and took 1,100 statements.

On August 11 1998, Rachel Tough died following repeated blows to the head with a hammer.

Rachel, who lived at home with her mother and brothers and sisters in Consett had received a telephone call from Thompson asking her to come round to 'help fix the washing machine'.

One week after her killing the body of Thompson was found hanging in woods less than a mile away, near the Hownsgill Viaduct, Consett.

At the inquest into Thompson's death in March, 1999, coroner Andrew Tweddle said he had 'no doubt' he'd killed Rachel.

Thompson has also been linked with the death of Emma Kennedy, 28.

The battered body of young mum Emma, 28, of Consett, was found at the foot of the 180ft Hownsgill Viaduct on New Year's Eve,1999.

While police wrote her death off as a suicide, her dad John insists his daughter was thrown from the bridge.

He believes Thompson's associates murdered her to silence her about JUlie's death.

John, 46, said: "The people who killed Julie Smailes murdered my daughter, I am convinced of that.

"Emma had been receiving telephone death threats warning her not to talk about Julie's murder.

"She had been a pal of John Thompson, one of the chiefs suspects who later killed himself. She told me he talked about Julie's murder. She became frightened. She said another man connected was on the phone constantly, she was terrified.

"Items of Emma's clothing and jewellery were found nearby the Viaduct - hanging from the same tree where John Thompson was hung."