"We tend to get this every year," he said yesterday. "I suppose it's a good mystery story, but we're tired of it. It isn't true."
Lewis said there was no evidence to support the claims.
Reports that a nurse apparently killed aboard the hospital ship HMAS Manunda was buried ashore in a grave that had since been lost could be true, but that was only one individual.
"If many more than the generally accepted figure of about 250 died, where are the bodies?" Lewis said.
"Mass graves have not been found. There are no witnesses who attest to large numbers being buried, necessarily weighted, at sea."
Nor could conspiracy theorists explain where, or how, the allegedly unrecorded deaths occurred.
Lewis said that despite the chaos of the raids, targeted ships kept good records and the names of those killed aboard the American destroyer USS Peary, the tanker British Motorist, the freighter Meigs and the seven others sunk had all been researched.
Ships damaged in the attack also kept good records.
On land, the damage in the first raid was not widespread: targets such as the Post Office and the police barracks listed all known casualties, and the attack was "not so large as air raids go".
"The much put-about phrase that 'more bombs were dropped on Darwin than on Pearl Harbour' is an irrelevance," Lewis said.
"The tonnage of bombs dropped on Pearl Harbour was greater, and the destructive power much higher."
More than 2000 people were killed in the Hawaiian raids.
Lewis said the bombers that attacked Darwin in the first raid were all single-engined aircraft with smaller bombs.
But Lewis said some of the stories were understandable: "Seeing death on a widespread scale, with hundreds more wounded, does cause psychological trauma."
Bodies were buried initially on the city's Mindil Beach, now famous for its sunset markets, and in other areas, but were later exhumed and reburied in formal grounds such as Adelaide River War Cemetery, off the Stuart Highway about 120km south of Darwin.
