A woman was attacked after she answered her door to a bogus salesman.
The 43-year-old opened her door on North Crescent, East Dene, Rotherham, to a man claiming to be selling goods.
But the woman told police he then attacked her - causing her to hit head and knocking her unconscious.
When she regained consciousness a few minutes later she saw the man leaving her home and later discovered that a number of items had been stolen.
Detective Chief Inspector Bob Chapman, leading the hunt for the robber, said: “Fortunately the woman was not seriously injured but is incredibly shaken and upset.
“This does appear to be an isolated incident however officers are making a number of enquiries as part of the investigation to identify the person responsible.
“I would urge residents to please be aware and alert, and to immediately report any suspicious behaviour or activity in their area to the police.”
The offender was black, of a medium build and around 5ft 7ins tall. He was between 20 and 25-years-old and spoke with a local accent.
He was wearing blue jeans, a black jacket and a light blue woolly style hat.