Police investigating the deaths of three prostitutes said they were concerned about a fourth missing woman.
Police have appealed to prostitutes to stay off the streets of Ipswich after three women were found dead and a fourth reported missing from the town.
Ipswich prostitute Paula Clennell, 24, has not been seen since late on Saturday, police said.
The naked bodies of Gemma Adams, Tania Nicol and a third woman have been found near the town in the past eight days.
Detectives are already investigating the deaths of three women whose bodies were found near the Suffolk town.
Suffolk Police said they were now looking for prostitute Paula Clennell, 24, last seen late on Saturday.
Gemma Adams, and Tania Nicol were found two miles apart in the same stretch of water. The naked body of a third woman was found in trees at Nacton on Sunday.
Asst Ch Const Jacqui Cheer urged all women in Ipswich, particularly during the party season, not to go home alone.
Detectives said the latest discovery was being treated as an "unexplained death".
In a direct appeal to prostitutes, she said: "Please stay off the streets, if you are out alone at night you are putting yourself in danger.
Reported missing
"Any information, no matter how trivial you think it might be, could be the key to moving this investigation forward."
Ms Adams, 25, and Ms Nicol, 19, worked together and went missing from the red light area of Ipswich.
Ms Adams, 25, and Ms Nicol, 19, worked together and went missing from the red light area of Ipswich.
Ms Adams vanished on 15 November and her body was found in a stream at the village of Hintlesham, Suffolk, on 2 December.
Ms Adams vanished on 15 November and her body was found in a stream at the village of Hintlesham, Suffolk, on 2 December.
Ms Nicol disappeared on 30 October and her body was discovered on Friday in the same stream at Copdock, near Ipswich.
Ms Nicol disappeared on 30 October and her body was discovered on Friday in the same stream at Copdock, near Ipswich.
Wooded area
Det Ch Supt Stewart Gull said: "While we can't formally link the discovery of the body at Nacton with the two murders, the facts speak for themselves."
Both were found naked and Det Supt Andy Henwood said they were treating the deaths as "linked investigations" and that there were "obvious similarities" between the disappearances and subsequent deaths.
He said Ms Clennell was reported missing by a friend.
He said it was "very rare" to have a linked murder investigation and they were now reliant on information from the public to help move the inquiry forward.
"We know that Ms Clennell uses a number of addresses in Ipswich and we are currently checking these to establish her whereabouts.
The Reverend Andrew Dotchin, vicar of Whitton, Ipswich, who knew Ms Nicol, said people were very worried.
"We would urge Paula or anyone who knows of her whereabouts to call us immediately so that we can be reassured that she is safe and well."
He said: "I think there is a great deal of concern that a serial killer is at large.
"There is a sense of concern for our town, a sense of concern for the girls that are still on the street."
Mr Dotchin said he came into contact with Ms Nicol about two years ago.
He said: "She was one of a number of youngsters who used to gather near the church. That was how I got to know her.
"For the little time I knew Tania I got a sense that she was a girl who was frightened about how her life was going to turn out."
Gemma Adams was last seen on 15 November
The third body was found by a woman out walking in a wooded area just off the A14 about two miles outside Ipswich.
Post-mortem examinations have been carried out on both murdered women but police said more tests were now needed and these could take up to six weeks.
Detective Chief Inspector John Quinton said there was no evidence either woman had been sexually assaulted and there were no obvious signs of injury.
The clothing worn by the two women on the nights they went missing has yet to be found.
Det Ch Insp Quinton said Suffolk detectives were liaising with colleagues in Norfolk where police had investigated the murder of three prostitutes in recent years and the disappearance of a fourth.
Police have also appealed for the clients of both Ms Nicol and Ms Adams to come forward.
