Norma Girolami who is aged 70 and from Elms Park, Cholmeley Park, Highgate, N6 was reported missing to police on Monday, 20 September.
As a result of police enquiries, officers became increasing concerned that some harm may have come to Norma.
As a direct result of those concerns the investigation has been passed to homicide detectives from the Met’s Specialist Crime Command.
Officers are conducting searches of several addresses and have contacted friends and relatives, but so far have been unable to locate Norma.
On Friday, 1 October two people were arrested in connection with the investigation.
A 39-year-old man was arrested at an address in Islington.
A 34-year-old woman was arrested at an address in Finchley.
Both were initially arrested on suspicion of fraud and false imprisonment, but both were subsequently further arrested on suspicion of murder.
They were both taken into custody, where the 39-year-old man remains. The 34-year-old woman has been released on bail to a date later this month
Detective Chief Inspector Kate Blackburn, said: “Norma has not been seen by her friends or family since the middle of August. As a result of our investigation we are extremely concerned that Norma may have come to some harm.
Her home shows no sign of her planning to leave, food was left in her fridge and she said nothing to her friends and relatives. This is completely out of character and as more and more time has passed, this has only added to our fears that some harm has come to her.
“In view of these concerns for her welfare, and to stop the anguish her friends and relatives are enduring, it is imperative that anyone with information contacts police. If anyone knows anything about where Norma may be, has witnessed anything from mid-August to mid-September in the area that Norma lived or if you know anything about what may have happened to Norma, then please contact police. Your information, no matter how trivial you might think it is, could be the vital information that helps us find Norma.
“Norma, if you are safe and well please get in touch with the police.”
Any witnesses or anyone with any information is asked to call police on 101 or contact via Twitter @MetCC. Please quote CAD 4006/01OCT
To give information anonymously contact Crimestoppers on 0800 555 111 or online at crimestoppers-uk.org.