An investigation has been launched to find out how a 48-year-old woman was left with serious head injuries.
The woman was found collapsed on the pavement close to the junction of Cranford Road and Nursery Lane in Kingsthorpe, at about 3.25pm on Friday, July 17.
But Northamptonshire Police are calling for witnesses to come forward as it is not clear how her injuries were caused.
She was conscious when she was found and was initially helped by police officers.
However she was then taken to hospital where she remains in a serious but stable condition.
A police spokesperson said the woman was white, aged 48, with frizzy blonde hair.
When she was found, she was wearing a black hat, black jacket, a grey and white striped blouse, jeans and white sandals.
Witnesses, or anyone else who knows anything about this incident are being asked to call Northamptonshire Police on 101 or Crimestoppers anonymously on 0800 555 111.