The women were found naked between 2 and 12 December
Inquests into the deaths of four women who were killed in Suffolk have been opened and adjourned.
The hearing at Ipswich Coroner's Court found no clear cause of death for Tania Nicol and Annette Nicholls.
Anneli Alderton was asphyxiated and Paula Clennell died from compression of the neck, coroner Dr Peter Dean said.
The inquest into the death of another victim, Gemma Adams, was opened last week. Police are continuing to question two men about the murders.
The first suspect, Tom Stephens, 37, was arrested on Monday. A second man being held has been named locally as 48-year-old Stephen Wright.
Both are suspected of killing all five women.
Dr Dean offered his condolences to the families of the murdered women, who were not at the hearing.
Det Supt Andy Henwood told the inquest Miss Nicol had left her home in Ipswich on 30 October to go to work as a prostitute in the town centre.
She failed to return home and was reported missing, he said. Her naked body was found on 8 December in Belstead Brook at Copdock, near Ipswich.
The naked body of Miss Alderton was discovered beside a road in the village of Nacton, near Ipswich, by a member of the public on Sunday 10 December.
Miss Clennell was reported missing in the early hours of 10 December after she went to work in Ipswich's red light district.
Mr Henwood said that on 12 December the naked body of a woman was discovered on the Old Felixstowe Road and was later identified as Miss Clennell.
Annette Nicholls was reported missing on 11 December and was last seen by her mother on 4 December.
When officers attended the site of Miss Clennell's body at Levington, the Suffolk Police helicopter discovered the body of a second naked woman nearby.
The inquest heard the body was later identified as Miss Nicholls. A post-mortem examination had been unable to establish the cause of her death.
Dr Dean paid tribute to the efforts of the police involved in the investigation and added: "We would still ask anyone who may have any information which may assist these officers to contact the police."
Suffolk Police said on Wednesday that officers had been given more time to question Mr Wright who is believed to work as a freight handler at the Port of Ipswich.
Magistrates had already granted police an extra 36 hours on Tuesday to continue questioning Mr Stephens.
Forensic teams have been searching an address in the London Road area of Ipswich where Mr Wright was arrested.
Former special constable Mr Stephens was arrested at his home at Trimley St Martin, near Felixstowe.
He is in custody at an unidentified police station in Suffolk.
Police have not confirmed or denied the identities of the people in custody.
Forensic scientists and police teams have been carrying out searches at Mr Stephens' home, in Jubilee Close, and his mother's home in the market town of Eye, Suffolk.
The five dead women were all found naked in rural settings, within 10 miles of Ipswich and close to the A14.
The body of Miss Adams, 25, who went missing on 15 November, was found in a brook at Hintlesham, Suffolk, on 2 December.
She had not been sexually assaulted but no cause of death was found.