Two more bodies have been found by police investigating the murders of three prostitutes.
A woodland area around the village of Levington, near Ipswich, in Suffolk, was sealed off by officers on Tuesday.
Police said it was likely the two bodies were those of two missing women - Paula Clennell and Annette Nicholls.
The area is close to where the body of Anneli Alderton was found on Sunday. The bodies of Gemma Adams, and Tania Nicol were also found near Ipswich.
Ms Clennell, 24, and 29-year-old Ms Nicholls, have not been heard from since Sunday.
Det Ch Supt Stewart Gull said: "The natural assumption is that these are the two missing women.
"These two bodies have been found not far from where Anneli was found and I fear the worst. They may well be Paula and Annette."
Suffolk police officers were called to Levington shortly after 1500 GMT after a member of the public reported seeing a body.
The force helicopter was scrambled and a member of the crew spotted a second body.
The site of the find is off the main Felixstowe to Ipswich road, close to a railway line, in a rural area close to Ipswich.
Suffolk Chief Constable, Alastair McWhirter, said the force had been taken by surprise by the speed with which the killings have occurred.
He said: "In the case of the Yorkshire Ripper, those murders took place over several years.
"This number of murders in such a short period of time is very demanding but we're putting resources in place to deal with it."
Mr Gull said: "We've formally linked the murders of Tania and Gemma on Saturday because of significant similarities, and they continue with Anneli, Paula and Annette.
"Clearly they were all prostitutes from Ipswich, they were found naked and in an open rural environment.
"We need to catch this person or persons as quickly as possible."
The bodies of three prostitutes were found earlier this month
Ms Adams' body was found on 2 December at Thorpes Hill, Hintlesham, near Ipswich.
Police divers recovered the body of Ms Nicol, 19, six days later from the same stretch of water at Copdock Mill.
The body of Anneli Alderton, 24, was found in woodland at Nacton on 10 December. She had been strangled.
Mr Gull said no further prostitutes had been reported as missing in Ipswich, but he urged prostitutes to stay off the streets.
"We have got three prostitutes murdered, now possibly another two. I do not know what stronger warning there can be to get off the streets as soon as possible," he said.