New CCTV images of four people that may have interacted with RAF airman Corrie Mckeague on the night he went missing have been released.
The 23-year-old was last seen alive on a night out in Bury St Edmunds, Suffolk, on 24 September.
CCTV showed him entering a bin loading bay known as the Horseshoe. A search of a landfill site in Milton, Cambridgeshire, failed to find him.
Suffolk Police said the people in the images could have new information.
They are not being treated as suspects or key witnesses in the case, the force said.
However, those pictured at the entrance of the Flex nightclub interacted with Mr Mckeague earlier in the night and might be able to provide some clues.
Another four other images, three of males and one of a female, have also been re-released to the public.
Anniversary of disappearance
Mr Mckeague, from Fife in Scotland, had been out with friends before becoming separated from them.
The last sighting of him was walking into the Horseshoe at about 03:25 BST.
Police established early on that Mr Mckeague was “known to sleep in rubbish” and his mobile phone tracked the same route as a bin lorry on the night of his disappearance.
An error in reporting the weight of the truck meant the force did not initially search the landfill.
A 20-week search of the site did not find his remains and was wound down.
To mark a year since his disappearance, police are setting up a “pod” in the town centre to “see if this can generate any new lines of inquiry”.
Det Supt Katie Elliott said: “The search for Corrie remains an active investigation.
“We would appeal directly to the public who were out in Bury St Edmunds exactly 12 months ago on the night he went missing and [who], maybe a year on, are once again back in the town centre this weekend.”