A large team of forensic officers have arrived at the scene of a XL Bully attack that claimed the life of a man in Shiney Row, near Sunderland.
The dog was "destroyed at the scene to ensure the safety of the public", and a second dog was also seized from the address as a precaution.
Northumbria Police said he was taken to hospital suffering from serious, life-threatening injuries but died later that evening.
Read more: Shiney Row 'XL Bully' attack: Murder investigation in Maple Terrace
A 44-year-old man was initially arrested on suspicion of wounding with intent to cause grievous bodily harm and was later re-arrested on suspicion of murder.
The dog, which police believe was an XL Bully, was destroyed at the scene.
Read more: Shiney Row: Residents recall aftermath of awful 'XL Bully' attack
Detective Chief Inspector Angela Hudson, of Northumbria Police, said: “While our investigation is at an early stage, we do believe those involved were known to each other.”
Linda Blyth, who lives in Maple Terrace, said she saw paramedics working on the injured man’s neck. The attack happened on grassy area behind her home, she said.
Police responded in large numbers and officers told residents to go inside.
Read more: Shiney Row: Sunderland 'XL bully' attack was 'chaos'
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She told the PA news agency: “We were told ‘go in, shut your doors’ and then I heard the gun shot.”
The dog was shot in the owner’s yard.
“I don’t know what set the dog off, everyone is speculating,” she said.
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