Students and staff at Hull University are devastated by the death of Libby Squire, according to the vice-chancellor and the president of the students’ union, as police said they were treating her death as a potential homicide.

The university has put in place extra measures to support students and keep them safe, including organising for students to walk in groups or with security staff if they want to.

The union president, Osaro Otobo, said: “The student community are absolutely devastated by this news, but now we want to pull together and support each other during this time.”

Squire’s body was found in the Humber estuary on Wednesday afternoon. She had been missing since the early hours of 1 February following a night out in Hull, and her disappearance prompted an intensive search lasting more than a month.

Facebook Twitter Pinterest Squire ‘captured the hearts of not just the people in Hull, but across the country’. Photograph: Family/PA

In a statement on Friday, Det Supt Martin Smalley of Humberside police 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 postmortem examination concluded late last night and at this stage we will not be releasing any results, for investigative and operational reasons.

“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.”

Otobo spoke to the university’s vice-chancellor, Susan Lea, in front of flowers and messages laid in tribute to Squire, who was 21, on campus.

She said: “The student body would like to pay their respects to Libby and her family. So, as a students’ union, we have a remembrance tree on our ground floor where students can write a note for Libby and her family, which will be passed on to them.

“They just want to show their respects. You can see from the tree, all of the flowers and the tributes. That’s what we want to do – just show how much we care.”

Asked whether students were worried about their security, Otobo said: “There’ll be some concerns about safety, but I want to highlight that this is such a rare occurrence, so now, as a students’ union, we highlight all the measures that you can take to be safe on a night out, including how to prepare your journey, make sure you book a taxi on a night out.”

Lea said: “It has been a difficult time. Students and staff are devastated by the situation and the way it has unfolded. But I think we’ve pulled together as a community.

“This a really close-knit community and we’ve been really heartened and moved by the way in which staff and students, the local community and the police have come together at a difficult time both in the search for Libby, but also to support one another.”

She said safety was an absolute priority for staff and students.

“We are absolutely committed to providing all the support we can to our staff and our students,” Lea said. “We are doing that in a variety of ways and I have an extremely strong team leading that.

“We have extra assistance available to our students through advisers. We also have schemes available so security will walk with them if they would like somebody to walk with them. And students have got together to form groups so they can walk in pairs.”

Lea also said there was extra mental health support available for students.