The 34-year-old died following the incident at the park in Hillson Drive, Portsmouth, shortly before 10.30am on Wednesday. A 20-year-old man has been arrested on suspicion of being the owner of the dog.
A Hampshire Police spokesman said: “We are speaking to people in the area and carrying out other lines of enquiry to establish how the man died.
“As part of our enquiries a 20-year-old man from Fareham has been arrested on suspicion of being the owner/person in charge of a dog dangerously out of control causing injury resulting in death.
“He has been released from custody without charge but remains under investigation while enquiries continue.”
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