Police hunting fugitive Ivan Leach believe he may have travelled by coach to London.
Leach caught a bus at Nottingham on October 20 and got off in London.
Officers from Lancashire are travelling to the capital to investigate and to distribute wanted posters.
The last confirmed sighting of Leach came from CCTV footage which shows 47-year-old Leach at a Barclay’s Bank cash machine in Nottingham city centre at 11.13am on October 20.
Police have also received more than 100 possible unconfirmed sightings.
Leach, also known as Lee Cyrus, went missing from North Sea Camp open prison, Boston, Lincolnshire on Tuesday, October 9 after going on day release and police forces across England and Scotland continue to work together in an effort to track him down.
Det Supt Withers said: “We believe that Leach travelled to London by coach in October and got off in the capital. We are making enquiries to try to trace him and I have sent officers to London in a bid to try to trace him.
“We are continuing to liaise with a number of other forces across England and Scotland and have a huge number of resources dedicated to tracking him down but we also need the public’s help.
“I want to reassure people that we follow up every potential sighting of him so I’d urge people to call police if you think you see him or know of his current whereabouts.
“I would also like to warn anyone who may be harbouring him that if they know where he is, and they fail to notify police, action will be taken against them.”
Anyone with any information should call police on 101 or Crimestoppers on 0800 555 111.