Merseyside Police said their investigation into the death of Mr Clarke is still ongoing and appealed for anyone with information to come forward.
Officers were called shortly after 8.30pm on Saturday and found Mr Clarke lying on the ground with the animal nearby.
An armed unit was called in to shoot the dog.
A friend of Mr Clarke suggested he could have been attacked because the dog could smell the food he was cooking for his dinner.
It was also suggested Mr Clarke had complained about the dog only the day before, and intended to report it to the police.
A spokesman for Merseyside Police said a post-mortem examination showed Mr Clarke died from "multiple injuries consistent with a dog attack".
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