A rampaging XL Bully dog mauled its owner before escaping from police and forcing a school to evacuate.  

Police officers were called in force to Gateley Road in Brisley, near Dereham, on Monday afternoon to reports that a woman was being attacked by a dog in the back garden of her home and was screaming for help. 

Officers found the victim - a woman aged in her 60s - being mauled by her pet XL bully called Denvor who weighed around six stone.

After officers pulled the dog off the woman, it escaped through the garden gate and was found around an hour later in the car park of Brisley Church of England Primary Academy in School Road - home to 75 pupils aged five to 11. 

Eastern Daily Press: Brisley Church of England Primary Academy was forced to evacuate after the XL Bully entered the car parkBrisley Church of England Primary Academy was forced to evacuate after the XL Bully entered the car park (Image: Newsquest)

According to police, a member of the public had managed to secure the dog to a post, with pupils and teachers still inside the main school building.

A spokeswoman for the school said the school car park was empty and the police asked for the staff and children to be evacuated to the field. 

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Belinda Allen, headteacher of Brisley Church of England Primary Academy, said: "Our school staff were alerted by the police that there was a dangerous dog and immediately actioned staff to clear the area.

"There was no immediate danger to staff or children within the school area."

Police contacted multiple veterinary practices for help to sedate the dog but none were able to attend. 

Eastern Daily Press: The XL Bully, named Denvor, was adopted from Dogs Trust Snetterton less than a month agoThe XL Bully, named Denvor, was adopted from Dogs Trust Snetterton less than a month ago (Image: Dogs Trust)

With the permission of the owners, the dog was destroyed.

Inspector Diana Woodage said: "This was a terribly sad and distressing situation.

"Officers were faced with an incredibly difficult situation when they arrived at the scene – a woman being viciously attacked by her dog and was very clearly injured and in some pain.

"In the interests of public safety and at the request of the owner, the dog was humanely destroyed. "

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The victim was taken to Norfolk and Norwich University Hospital with multiple injuries which are not life-threatening. 

Denvor was adopted from Dogs Trust Snetterton less than a month ago and had "no history of aggression", with the trust believing him to have "settled well into his new home".

A Dogs Trust spokeswoman said: "Our priority at this time is to provide as much support as possible to people affected by this incident, and we will be undertaking a thorough investigation."