An 81-year-old woman suffered a broken hip when she was dragged to the ground by a teenage robber near her home in Manchester.
The woman was walking with her son near Briscoe Lane, Newton Heath, when a teenager grabbed her handbag and pulled her down at 0010 GMT on Sunday.
She was taken to hospital where she remains in a serious but stable condition, police said.
The offender ran off with her bag containing some cash and a bus pass.
He is described as white and in his mid-to-late teens.
Det Sgt Darren Scarr said: "The victim is an elderly woman who has been targeted by an opportunistic, spineless thief.
"As a result of being dragged to the ground by the robber, she has suffered an extremely serious injury and we are doing all we can to identify the person responsible.
"The offender is probably unaware just how seriously injured the victim is and I would urge him to come forward now and speak to us."