Police looking for missing Hull student Libby Squire say they are keen to speak four people pictured on newly released CCTV.
Officers believe the people, captured at the junction of Oak Road and Clough Road between 1.13am and 2.34am on Friday 1 February, may be able to help with the search as it approaches the three week mark.
The clip shows a cyclist, a pedestrian and a pair walking together in the early hours of the last day Miss Squire was seen.
Leading the investigation, Detective Superintendent Martin Smalley said: "These four people are potentially witnesses who we need to identify and speak to as part of the investigation.
"While the footage isn't clear enough for anyone to recognise who they may be, the four people in the clips will know if they were in that area at the times given and I would ask them to please come forward to assist with our enquiries.
"The four people may have seen or heard something that could be vital to the investigation. If you believe you are one of them, or you know who they might be, please make contact with us on 101."
Timeline of events around Libby's disappearance
Libby was last seen at the junction of Beverley Road and Haworth Street at around 12.05am on February 1 while wearing a black denim skirt and faux leather jacket and distinctive trainers, according to police.
Five days later, Pawel Relowicz, of Raglan Street, Hull, was arrested and questioned on suspicion of abduction. He remains a person of interest, police have said.
He appeared before magistrates charged with a number of offences unrelated to Miss Squire’s disappearance and has since been remanded in custody.
Officers have previously released several pieces of CCTV related to this student's disappearance.