An investigation has been launched after a pensioner suffered a broken pelvis when she was thrown to the ground in Saltwells Nature Reserve on Tuesday.
At around 4pm, the 84-year-old woman was walking through the reserve with a friend when she was approached by a man who pushed her to the floor and stole her handbag.
The woman suffered a fractured pelvis and was taken to hospital where she remains in a stable condition.
The man is described as white, was dressed all in black and wearing a face mask.
The elderly woman remains in hospital with serious injuries and has been left very shaken by the incident.
Officers would urge anyone who witnessed the attack or has any information, no matter how small, to get in touch.
Anyone with information is asked to contact police via Live Chat between 8am and midnight, or call 101 anytime giving reference 20DY/170947F/20.