They have renewed their appeal for witnesses who may have spotted any of three men acting suspiciously.
Mrs Williams, 29, was found on 21 August by her husband Tim when he returned to their home in Rotherhithe after a week away working.
Two of the men were separately seen looking over the garden fence between 1.10pm and 2pm that day. One was described as of Mediterranean or heavily suntanned appearance, early 20s, 5ft 9in tall, with an athletic build and black hair, cropped short at the sides and curly, possibly gelled, on top.
The second was white with mousy brown hair, and the third, seen running away some time after 4pm, is of a similar description to the second. Police said that the second and third sightings could refer to the same person.
Detective Superintendent Gordon King, leading the investigation, yesterday told his Crime Squad officers to saturate the area north of the Old Kent Road with artists' impressions of the two men.
He said police were working on the theory that the men were local, and possibly burglars.
Anyone with information is asked to call the incident room on 407 4759 or Crimestoppers on 0800 555111.Reuse content