Police searching for Owami Davies have released new CCTV footage showing the student nurse walking through the Norbury area of south London wearing a distinctive red top.
Detectives believe it could be the last recorded image of the 24-year-old from of Grays in Essex and are urging anyone with information to come forward.
The footage was recorded on Thursday, 7 July and shows Owami wearing a dark jacket, red t-shirt, light grey joggers, slider shoes and carrying a white handbag over her shoulder.
Police say she was walking north on London Road away from West Croydon.
"I would ask members of the public who were in this area, or nearby roads, to think back and call us if they remember seeing Owami and please do not underestimate how important you call could be," said Detective Chief Inspector Nigel Penney.
"CCTV enquiries are very detailed to ensure nothing is missed. Every time a person reaches a junction it can mean that several new roads have to be examined to see which way Owami went," he added.
Owami was last seen just after midnight in Derby Road, West Croydon, south London, on Thursday July 7.
An unconfirmed sighting placed her in nearby Clarendon Road at about 7am later that morning.
The Metropolitan Police said she had left her family home in Grays three days earlier on Monday July 4.
Officers have arrested five people – two on suspicion of murder and three on suspicion of kidnap.
The most recent was a 27-year-old man arrested on suspicion of kidnap on Saturday.
"I can assure our community that all we can do to find Owami is being done. We are working closely with our colleagues in Specialist Crime, who are used to dealing with large, complex investigations and we are providing them all the assistance we can in this extensive inquiry," said South Area Commander Chief Superintendent Dave Stringer
"Everyone, I am sure, is hoping that Owami is safe and well and this nightmare for her friends and family will finally end," he added.
Investigators have previously appealed for the driver of a white van that was parked in Derby Road when Owami was last seen to come forward.
She and a man crossed the road just as the van pulled out.
Owami’s mother Nicol Davies has made public appeals through the police for help finding her daughter.
She said: “This is such a terrible time for all those who love Owami and I am pleading for anyone who can help find her to contact police.
“Every day we hope to hear the news that Owami is coming back to us, your help might make it so.”
Miss Davies was nearing the end of her studies and had secured a job with Guy’s and St Thomas’ health trust, her mother said.
She had worked in A&E during the Covid-19 pandemic and was interested in doing research on diseases.
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know...