A member of the public has told police they’ve seen a body in the Waikato River, four days after an Australian tennis coach went missing in the New Zealand city of Hamilton.

Police are investigating the report of a body in the river, after a member of the public called them about it at 7am on Thursday.

Police have yet to verify the sighting.

Melbourne man Paul Arber, 38, was last seen in the Waikato River in the early hours of Sunday morning.

He had been in Hamilton with a large group of children for a tennis tournament.

Two people saw a man, who said his name was Paul, in the river as they walked over Victoria Bridge on Sunday morning.

They offered to take him back to his accommodation but after he went with them up to the bridge, he changed his mind and walked off – back to the river.

Police say he was exhibiting behaviours best described as being out of character shortly before he disappeared.

His parents, Sam and Richelle, have described their son as a gentle and spiritual person.