The University of Hawai'i yesterday said it has found "hundreds" of munitions on the ocean floor about six miles south of Pearl Harbor, as it continues to use deep-diving submersibles to search for tons of chemical weapons dumped during and after World War II.

The military, with UH's help, plans to test water and sediment samples from the sticky mud bottom in about 1,500 feet of water for the presence of chemical agents.

Researchers on the UH submersibles Pisces IV and V haven't located the main cache of chemical weapons, but still have 10 more dives as part of 2 1/2 weeks of underwater study. Remotely operated vehicles also are being used.

So far, some munitions have been identified as probably being fragmentation bombs because of the presence of what look like small parachutes that would slow the ordnance in flight, officials said.

There also appear to be incendiary bombs, and the presence of double bands on some munitions that could signal chemical agents, though there has been no positive identification of any chemical weapons, officials said.

"We may identify the mother lode. I don't think we've found the mother lode if you are asking about the chemical munitions that were all sea-disposed," said J.C. King, who is with the Office of the Deputy Assistant Secretary of the Army for the Environment, Safety and Occupational Health.

A 2007 report to Congress said 2,558 tons of chemical agents were dumped at three deep-water sites off O'ahu, including lewisite, mustard, cyanogen chloride and cyanide.

Included in the ordnance dump were 15,000 M70 115-pound mustard bombs, 1,100 M79 1,000-pound cyanogen chloride bombs and 20 M79 1,000-pound cyanide rounds. The weapons are in waters up to 10,000 feet deep.

UH and the Army — which was directed by Congress to investigate the dumping — held a press conference yesterday aboard the support vessel Kaimikai O Kanaloa at Snug Harbor to detail the progress on the eight dives so far.

The dives are part of the Army's ongoing assessment of the health and environmental effects from the old bombs, which were ditched by the military at sea as excess munitions piled up toward the end of World War II.

The deep-water O'ahu sites are five to 10 miles south of Pearl Harbor and Wai'anae.

UH researchers are taking water and sediment samples to see if there are metals from the munitions or any residue of chemical agents, as well as to visually observe the effects of more than 60 years on the containers. Shrimp and onaga from the site also will be tested, officials said.

Tim Blades, with the Army's Edgewood Chemical Biological Center in Maryland, said chemical agents such as mustard are not water-soluble in the 43-degree depths.

Mustard is heavier than water and it "forms a nodule and it grows a skin, and it's really tough then for it to get exposure to the air or your body," Blades said.

UH's principal investigator, Margo Edwards, said a towed detection system was used in 2007 to look at 40 square miles of ocean bottom at the site south of Pearl Harbor from about 150 to 200 feet above the sea floor.

Rows of "black dots" that appeared were investigated further to identify munitions that were rolled off the sides of barges.

King, who is with the Army, said munitions have been observed in both corroded and marine-encrusted, but uncorroded, states. It may take a year for the water, sediment and marine life analysis to be completed, officials said.

Officials said the Army is spending about $3 million for the UH research, and $4.75 million to investigate the separate removal of nearshore munitions near Wai'anae.