NEW DNA evidence might be the key to solving a murder that has baffled police for 20 years.

Mother-of-three Janet Brown was found dead at the bottom of the stairs of her family home on Tuesday, April 11, 1995.

Her hands were cuffed behind her back and packaging had been stuffed in her mouth.

The 51-year-old Oxford University research nurse had been repeatedly struck on the head with what police say was a heavy object like an iron bar.

A post mortem examination confirmed head injuries as the cause of death.

Police said she was killed between 8.15pm and 10.15pm the night before, when she was home alone, 20 years ago today. A window had been broken but nothing was stolen.

Officers said the attack was not of a sexual nature.

Her husband Graham Brown, a research scientist, was in Switzerland at the time and their eldest children Zara and Ben had moved out of home.

Their 17-year-old daughter Roxanne was staying with a friend that night and the last person who spoke to Mrs Brown was a friend who called at about 8.15pm.

Her body was found the next morning by a builder and his son who were doing work at the home, a luxury farmhouse on Sprigs Holly Lane, Radnage, near Chinnor.

Despite Thames Valley Police getting statements from some 2,700 people and a Crimewatch appeal which prompted 80 calls, the case was never solved.

But now the force said they had used the latest technology to extract a tiny amount of DNA from a piece of evidence found at the original crime scene and used that to build up a full profile of the person it came from – who may be the killer.

Police held a press conference with Mrs Brown’s daughters yesterday to put out a fresh appeal and offered a £20,000 reward for evidence which leads to an arrest.

Head of the major crime investigation review team Peter Beirne said the force planned to get DNA swabs from some of those 2,700 people originally spoken to in the case, starting with a tranche of 20.

But he said the force would also consider a “mass screening” of the area around Chinnor if necessary to nail down the source of the genetic sample.

Mr Beirne could not reveal exactly what the item was that DNA has been taken from but he said it had been kept in quarantine since the original investigation.

After 20 years, he said aspects of the case still puzzled police.

He said the method of entry was “very strange” because one pane of glass had been removed from a downstairs window while a second pane was smashed.

Initially police thought there was a link with the shooting of university scientist Michael Meenaghan who was killed in the kitchen of his home at Monks Close, Blackbird Leys, in December 1994. They have since confirmed they don’t believe there is a link.

Mrs Brown’s daughters Roxanne and Zara, now 37 and 42, read out a statement at the press conference appealing for people to come forward.

They said: “Our mum’s murder was planned and brutal and the horror of her death stays with us every day.

“She was attacked and killed in our family home – a place where we should all be safe. She was a kind and loving person and her death broke our hearts.”

Mr Beirne said he was confident the killer was not either of the builders or any of the family.

Also unsolved

  • Boars Hill couple Warren and Elizabeth Wheeler, 83 and 79, were found battered to death in the living room of their cottage in October 1973. Both had been beaten with a weapon but it was never found.
  • Finnish hitchhiker Eila Karjalainen’s decomposing body was found dumped in a wood on the Blenheim estate in November 1983. The 23-year-old had been strangled and her body lay undiscovered in Kings Wood, Woodstock, for three months.
  • Taxi driver Leonard Gomm was stabbed to death in a country lane in Bletchingdon four hours after he set out to pick up a customer in June 1990. A lorry driver found the 75-year-old dad-of-three on a grass verge with a stab wound to his heart.
  • Oxford University research scientist Michael Meenaghan was shot dead through the window of his Blackbird Leys home in 1994. Police never established an obvious motive for the killing.
  • Oxford mother-of-four Nasreen Akhtar was strangled at her home in Cobden Crescent, Oxford, on March 30, 1995. A £10,000 reward was put up six years after her death but the 29-year-old’s murder remains unsolved.