The death of university student Libby Squire, whose body was found in the Humber Estuary on Wednesday, is being treated as a “potential homicide”, Humberside Police said.
Detective Superintendent Martin Smalley said: “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.
“We have to protect the integrity of the investigation, which is live and very much active and ongoing, with one man who remains under investigation.”
He added: “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.”
The 21-year-old was last seen just after midnight on Friday 1 February on Beverley Road, close to the junction with Haworth Street in the East Yorkshire city.
Her body was discovered close to Spurn Point around 3.30pm on Wednesday and taken to Grimsby docks.
Squire, from High Wycombe, Buckinghamshire, was studying philosophy at the University of Hull when she disappeared.
Around 50 detectives worked on the case and a 24-year-old man was arrested on suspicion of abduction.
Pawel Relowicz, of Raglan Street, Hull, has been remanded in custody having appeared in court on unrelated charges of burglary, voyeurism, outraging public decency and receiving stolen goods.