An American newspaper has published a classified memo revealing stockpiles of weapons were kept in New Zealand during the war, then dumped at sea.
The US Army has admitted dumping 29,000 tonnes of chemical warfare agents and 400,000 mustard gas filled bombs and rockets off its own coastline.
But the newspaper's investigation has found there is much more than that in the coastal waters of other countries, including New Zealand, where one dumping was photographed.
The article also backs up claims by New Zealand researcher Owen Wilkes two years ago that chemical weapons were stored in the country and then disposed of.
"As soon as the war was over they couldn't wait to get rid of that stuff and dump it in Cook Strait, and then just forget all about it... and they obviously forgot about it very successfully," Wilkes told Sunday in 2003.
It has also been suggested government researchers turned up at the national archives in America two years ago looking for information on the chemical ocean dump sites, but none of the government departments One News spoke to knew of the research.
Last year a stash of mustard gas shells from the same era were found in the Solomon Islands. The Americans removed 90 projectiles, but locals say many were left behind.
The New Zealand Ministry of Foreign Affairs say it is not aware of weapons being dumped in our waters, but has alerted the New Zealand embassy in Washington.