However, a specialist marine unit has combed the icy depths of a large pond in the neighbouring Oak Road playing fields, while the Beverley and Barmston drain which runs behind her house also yielded no clues.
Detectives are said to be keeping an “open mind” about the circumstances of her disappearance, but the possibility it could have sinister undertones will now likely be hanging over them.
This prospect has caused anxiety on campus, with some students reported to be walking home in pairs.
Yesterday, the university acknowledged students may be “feeling worried” about last week’s developments and advised them that support staff were available if needed.
Chief Superintendent Phil Ward said: “While the investigation has been treated as a missing person inquiry, we continue to keep an open mind as to the circumstances surrounding Libby’s disappearance.
“We have had specialist officers, detectives and specialist teams carrying out numerous actions and enquiries, searches and following up leads since the report of Libby’s disappearance in the early hours of Friday, February 1.
“While her location is not yet known, this does not automatically mean she has come to any harm, but we must carry out a thorough investigation and explore all possibilities.”
Ms Squire’s parents, Lisa and Russ, travelled to the East Yorkshire city on Tuesday and last night released further information about their daughter.
They described a “sociable” and happy young woman who enjoys reading, travelling and music concerts.
Their statement added: “Libby decided to come Hull University when she fell in love with the city. She accepted an offer at the University before even visiting as she was so sure she would be happy here.”
The couple also thanked well-wishers for their support and kindness since her disappearance.