Advances in DNA testing have proved that the same man is responsible for four rapes, which all happened at knifepoint.
Police are convinced that he is also responsible for a further two rapes and an attempted rape. The attacker's usual method is to break into houses late at night and threaten his victims with a knife. The attacks took place in Northampton, Reading, Leamington Spa in Warwickshire, and Milton Keynes between 1984 and 1990.
Police have kept secret the full details of Operation Quicksilver, which covers three force areas, but improvements in DNA analyses have prompted a fresh appeal for information.
The women who were raped are also said to be determined to see their assailant put behind bars. They have spoken of about the horror and long- term effects of being attacked.
Between July 1984 and April 1987, five attacks took place on young women alone in their homes in Northampton.
In one case, a 25-year-old woman was awoken and threatened by a man who said: "Shut up, if you scream I'll use this, I'll cut your throat".
A second woman managed to fight off the man. All the women described him as a black man in his late teens or early 20s.
Two years later, a 28-year-old woman was assaulted in her bedroom in Milton Keynes at 4am. A year later the rapist struck in Reading.
The final attack was in July 1990 when a 34-year-old woman was raped at her home in Leamington Spa.
A DNA profile linked the last three rapes to the same man.
Late in 1997, developments in DNA testing revealed that the first assault in Northampton also matched.
One of the rape victims told the police: "It's not just my life he affected, it was family and friends. I had to move. I hated being in the house."
In appealing for witnesses for new information, Detective Superintendent Chris Cross, of Northamptonshire police, said: "These were terrible experiences and all the victims have told us that even after this time lapse they want this man to be caught.
"He must not be give the opportunity to reoffend."
The police can be contacted on 01604 700700.Reuse content