A female police officer is recovering from her injuries after she was violently attacked in the street by a 15-year-old girl.
Members of the public had to intervene to stop the assault in Windermere, Cumbria, in which the officer was repeatedly punched in the head and upper body as she lay on the ground.
The incident took place while the officer was on lone patrol in the Main Street area at about 9.50pm last Friday.
The officer had been approached by a 15-year-old boy who reported he had been assaulted by another youth nearby after he had been knocked to the ground.
Cumbria Police said the officer was then surrounded by a large group of teenagers, including an "aggressive, drunken" 15-year-old girl.
The girl was arrested and "a violent altercation" then took place with the officer being attacked on the ground.
A police spokesman said:
The officer is recovering at home from her injuries but is not fit to return to work, police added.
Police have recovered video evidence via social media websites but would like anyone with any footage obtained at the time to contact police.
Anyone with information should call Cumbria Police on 101 and ask to speak to Dc Jack Montague.