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IPSWICH - British police hunting a serial killer in Ipswich have confirmed prostitute Annette Nicholls as the fifth victim.
Nicholls, 29, was last seen on December 5, a week before her naked body was found dumped in countryside.
"We are treating this as murder and are linking it to the other four recent murders," Detective Chief Superintendent Stewart Gull told a news conference.
"The launch of a fifth murder inquiry in such a short space of time is unprecedented for the Suffolk Constabulary."
A post mortem failed to reveal how Nicholls died and more tests are to be carried out.
Police received 1,800 telephone calls from the public in the last 24 hours.
Prostitutes in eastern England are being offered financial help to stay off the streets as police step up their hunt for the killer.
Some prostitutes have ignored police warnings and carried on working, many to feed drug habits, despite the discovery of five bodies in less than two weeks.
Experts were carrying out toxicology tests on the bodies of two of the victims, Gemma Adams, 25, and Tania Nicol, 19, to see if they were drugged before they were killed, police said, but the test results will not be known for weeks.
Media reports have speculated the women may have been drugged because their bodies showed no obvious signs of injury or struggle.
The murderer has been dubbed the Suffolk Strangler, although the precise way all the women died is yet to be established.
Anneli Alderton, 24, was strangled and Paula Clennell, also 24, was killed by "compression to the neck", detectives said.
Nicol's parents appealed for help in finding the killer of their "caring, loving" daughter.
In a statement, Jim Duell and Kerry Nicol said they had lost their daughter to a "secret world" of drugs.
"Tania was a lovely daughter," Duell said, reading from the statement. "She was a caring, loving, sensitive girl who would never hurt anyone.
"Unfortunately, drugs took her away into her own secret world -- a world that neither of us were aware of.
"Tania has been taken by someone who needs to be found. We ask for anyone who knows this person or persons to come forward and contact the police."
No one has yet been arrested or questioned as a suspect, but police were seeking a number of people to help with their inquiries.
"We know they were all working girls, they knew one another. I think there is likely to be some crossover as far as clients are concerned," said Detective Chief Superintendent Stewart Gull.
"There are a number of people of interest to us."
- REUTERS
