Three women have been found dead since Dec. 2 around Ipswich, 70 miles northeast of London. All three bodies were naked. Police have confirmed that the first two had not been sexually assaulted.
Two of the bodies were found a few miles apart, one in a stream and one in a pond. The third was found in woodland several miles away.
Detective Chief Superintendent Stewart Gull said a serial killer may be responsible.
"We are keeping an open mind. We may be looking for one perpetrator, there may be more," he said.
The three victims are Gemma Adams, 25, whose body was found Dec. 2; Tania Nicol, 19, whose body was found Friday; and a 24-year-old woman, not yet formally identified, whose body was found Sunday.
Adams had not been seen since Nov. 15, and Nicol had been missing since Oct. 30, police said.
The third death "is a deeply disturbing development," Gull said.
"While we can't formally link the (cases), the facts speak for themselves."
A fourth woman, 24-year-old Paula Clennell, was reported missing Saturday.
Assistant Chief Constable Jacqui Cheer urged prostitutes to stay off the street, and to help police with any information they have.
"If you are out alone at night, you are putting yourself in danger at this time," she said.