The death of Hull student Libby Squire is being treated as “a potential homicide”, Humberside Police has said.
The 21-year-old’s body was found in the Humber estuary on Wednesday, seven weeks after she went missing following a night out on 1 February.
Detectives said she could have been killed but “would not be releasing results of a post-mortem examination for investigative reasons”.
Det Supt Martin Smalley said “one man remains under investigation”.
He said: “In regards to our investigation, while we have considered throughout the missing person inquiry that Libby may have come to some harm, Libby’s death and the recovery of her body now leads us to solely investigate as a potential homicide.
“The post-mortem examination concluded late last night and at this stage, we will not be releasing any results for investigative and operational reasons.”
An inquest into her death is due to open and adjourn on Monday.
Det Supt Smalley said specially trained officers were continuing to support Ms Squire’s family.
“Our thoughts remain today with Libby’s family and friends at this incredibly sad and devastating time for them,” he said.
“The loss of a loved one is always an upsetting and traumatic experience to go through, but the circumstances surrounding Libby’s death will only intensify the heartache for her family.
“Libby captured the hearts of not just the people in Hull, but across the country, and as I have said before, the support shown has been overwhelming and my sincerest thanks to absolutely everyone who has been involved.”