Suffolk police officers have been scouring a road in Bury St Edmunds in the search for Fife man Corrie McKeague.
Mr McKeague, an RAF serviceman from Dunfermline, was last seen in Bury St Edmunds during the early hours of Saturday September 24.
The 23-year-old had been on a night out in the town, which is a few miles from his base at RAF Honington in Suffolk.
On Tuesday morning, Suffolk Constabulary closed a mile and a half stretch of the A14 to the east of the town to allow the roadside to be searched.
Officers were expected to shift their efforts to Beck Row, which is 16 miles north west of Bury St Edmunds, later on Tuesday.
Police have seized 1,100 hours of CCTV footage from the local authority, businesses and individuals in an attempt to find Mr McKeague.
Despite a high profile campaign for information about his whereabouts, there have been no positive sightings of him.
It was initially believed Mr McKeague had attempted to walk back to his RAF base and roadsides between Bury St Edmunds and Honington were combed.
The search has since been widened and has involved RAF personnel and volunteers from Suffolk Lowland Search and Rescue, and National Search And Rescue Dogs Association.
Examination of data from his mobile phone has led to the suggestion he made a 28 minute journey to the Barton Mills area, which is near Beck Row, around the time he went missing.
Mr McKeague’s mother Nicola Urquhart has not ruled out the possibility he got into a stranger’s car.
Detective Superintendent Katie Elliott from Suffolk Constabulary said: “We have to keep an open mind as there is no key line of enquiry to take us in any one direction.
“We can’t rule anything out and therefore we have to continue to investigate all possibilities.
“Despite extensive searches, CCTV viewing, media appeals and many behind the scenes enquiries we still do not have a lead which takes us forward.
“Many theories are being explored and work is ongoing to trace everyone who was in the area around the key time as they may have information that may help.
“Officers have been working to locate all individuals and vehicles seen in the area in the early hours and have spoken to dozens of people, however we know there are still some who haven’t come forward or been traced and we would continue to ask anyone in the vicinity that morning to come forward.
“We have received support from many people in this work and we are grateful to all those who are assisting. It is important that we systematically work through all the information that has come into the enquiry and this work is continuing.”