Detectives searching for a missing oil executive have released CCTV images of a man they want to speak to in connection with the investigation.
Carole Waugh, 50, has not been seen by her family since April and concerns are growing after a fraudster tried to sell her flat in central London by posing as her brother, Chris.
Financial activity linked to her identity has also grown "incrementally more suspicious" since she vanished, Detective Chief Inspector John McFarlane said.
At least three women have tried to impersonate her - one at the Westfield shopping centre in west London on 13 July.
A man has previously posed as her brother at her flat in Marylebone, central London, in an attempt to sell it.
Waugh's 53-year-old brother, who lives in Cumbria, said it was "a very distressing moment" to discover the conman had posed as him.
On Thursday, Scotland Yard released the images of a man outside a branch of Sainsbury's in Crown Road, Enfield, north London, on 10 July, where one of Waugh's bank cards was used.
Police are appealing for anyone who has known Waugh since she moved to London in 2008 to come forward.
She is originally from Durham, and since her mid-20s had spent time living in Libya and London.
A "significant amount" of the businesswoman's personal property has gone missing, but McFarlane would not reveal what has disappeared.
Waugh, described by police as "a successful businesswoman", worked for Veba Oil in Libya for a number of years.
She was "very frugal and careful" and bought property in Harrowby Street, Marylebone, where she was living when she went missing.
She last contacted her mother about a week after leaving Cumbria on Easter Monday and since then nothing has been heard from her.
Waugh would always contact relatives, even while she was living in Tripoli, her brother said.
"Even when she was in Libya you would get a weekly or a fortnightly phone call to reassure everybody that everything was all right.
"If she had been out to Libya and returned on several occasions, whatever the rest of the world, especially the UK or London throws at you, it's not going to be as difficult I'd have thought as Libya.
"That gave us an amount of comfort, that she was worldly wise and very comfortable in London."
A sighting of her in London on May 4 is unconfirmed.