Major crime squad detectives believe missing mother Helen Rocha was picked up from her Willagee home by a man driving a small white car on the day she was last seen alive.
They have released an image of a small white hatchback similar to the one they believe she was in when she and the man travelled to somewhere in Parmelia, Orelia or Kwinana, just before noon on September 26.
They have previously said she left the home with a man but had not revealed details of the vehicle. Police know who the man is but have not released any other details about him.
Major crime squad detectives are treating Ms Rocha’s disappearance as a suspected homicide.
Detectives searched Henderson tip on Tuesday but would not say why or whether they found anything.
They have previously searched a Parmelia home and bushland around Kwinana train station as part of the inquiry.Police have urged anyone who thinks they have seen Ms Rocha or the vehicle described, or has any information about her disappearance to call Crime Stoppers on 1800 333 000.