Officers are carrying out door-to-door inquiries as they search for Libby Squire, 21, who disappeared on Thursday night.
At least 70 officers were out searching for the University of Hull student through the night on Friday.
Humberside Police held a press conference today (Saturday) to update the public on the ongoing search.
She was reported missing after getting into a taxi outside the Welly club in Hull at around 11pm on Thursday.
Miss Squire was then spotted at around 11.45pm by a motorist who got out of his car in order to help her on Beverley Road near the junction with Beresford Avenue.
Speaking during the press conference today, Superintendent Simon Gawthorpe, leading the search, said: “As you know, we have been conducting some significant searches overnight for Libby, who was a student at Hull University."
He said some 70 officers were involved in searches overnight for the student.
Supt Gawthorpe added: "Despite these efforts, we have still not located Libby and as you can imagine we are extremely concerned for her welfare.
"Officers are out again today searching for her and we really hope that we find Libby safe and well.
"I urge anyone knows anything about her whereabouts to come forward and speak to us as soon as you are able."
He asked people living in the area to check their gardens and outbuildings.
Miss Squire is described as being 5ft 7in, with shoulder-length brown hair.
She was last seen wearing a black long-sleeved top, a leather jacket and a black denim skirt with lace.
Anyone with information is asked to call police immediately on 101.