Two women, aged 27 and 28, have been arrested on suspicion of an offence under the Dangerous Dogs Act.
It follows the death of a 79-year-old man in the Clubmoor district of Liverpool after a dog attack.
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The victim reported Samantha Watt to police in July after she discovered the photos had been put up on her Facebook page.
The roof and floors collapsed during the blaze at the property, one of Britain's finest Palladian mansions.
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