A 90-year-old man is being questioned by police after the death of his 83-year-old neighbor on the footpath outside his suburban Melbourne home.

The victim, Michael Di Berardino, was found by his wife Gemma about 1 p.m. on Monday (9 a.m. Sunday ET), and called emergency services and family members.

The Herald Sun reported Mr Di Berardino was struck on the head with a stick or piece of steel by his neighbour, who he had been locked in a decades-long dispute with.

The two men allegedly argued yesterday over allegations the neighbour poisoned Mr Di Berardino's garden.

His son, Angelo Di Berardino, said he had tried over the years to speak with his neighbour’s family and his wife to resolve the argument, which began 47 years ago.

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