Police are investigating the mysterious death of an elderly man in a Bay of Plenty lake.

The body of Pukehina man Edward MacDougall, 77, was recovered from Lake Rotoehu near Rotorua by the police national dive squad today, three days after he went missing.

Mr MacDougall had been seen wearing a lifejacket when he set out for a fishing trip, but it had been found separate from his body along with the boat.

Rotorua Police senior sergeant Malcolm Collins said police were trying to establish what had happened - and why Mr MacDougall's lifejacket had been removed.

Advertisement

"That'll be one of those mysteries," he said.

"It would appear he had the life vest on but it was not done up properly, and that's come off, and he's been recorded as not being a strong swimmer."

Mr Collins said police had notified Mr MacDougall's family, and the death had been referred to the coroner.