The inhabitants of a Caribbean island which the US navy has used for 60 years as a bombing range, including firing depleted uranium shells, are seeking $100m (£68m) in damages for an abnormally high cancer rate.
Figures compiled in 1990-94 show that the 9,300 islanders of Vieques are 27% more likely to get cancer than those on Puerto Rico, just to the west.
But Dr Rafael Rivera-Castao, who lives on the island, says the rate has risen since then.
"I estimate that the cancer rate here is now 52% more than the Puerto Rico average."
The navy says the island offers the only terrain suitable for its military exercises.
John Arthur Eaves, the lawyer pressing for damages for one-third of islanders, said "I think $100m may turn out to be at the lower end of the scale of what we might get from the navy.
"We have already spent $7m on preparing this case, which we wouldn't have done if we didn't think we had a very good chance of winning."
Nilda Medina, of the Committee for the Rescue and Development of Vieques, said: "For years we have denounced the relationship between the military contamination and the exaggerated levels of cancer on Vieques.
"The heavy metals and other chemical components from explosives dangerous to human health combined with the radioactive uranium projectiles jeopardise the life of Viequenses today as well as future generations."
There was no way to guarantee that the next bomb would not hit one of the uranium shells, dispersing radioactive particles into the air.
Vieques became a cause célèbre 21 months ago after a misdirected shell killed a civilian security guard, and became the catalyst for a re-examination of Puerto Rican relations with the US.
Puerto Rico has been a territory for more than a century and its commonwealth status gives islanders US citizenship, albeit with reduced rights and duties: they cannot vote in presidential elections and do not have to pay federal taxes.
In the most recent referendum on the issue they rejected the idea of becoming the 51st state, but few of them have any interest in independence, despite a new Puerto Rican self-confidence reflected in the success of its sportsmen and such musicians as Ricky Martin.
Anti-American slogans are daubed throughout Vieques, an 18-mile long island on which civilians are confined to the middle third. Yesterday, as every Sunday, protesters rallied in the main town, Isabel Segunda, before driving in a convoy around the island blowing car horns and protesting through loudhailers.
Quite apart from the indignity of their existence on a virtually occupied land, they claim that the navy's presence prevents the development of the island, where tourism is among the few sources of income.
The bombing was halted after the death of the security guard when dissidents camped out on the range, defying the US and its allies, including Britain, to carry on.
They were removed last May after an agreement with Bill Clinton for a referendum in November on whether the navy should stay or go in 2003. President Bush, eager to show empathy with Hispanics, said he would respect the deal.
Bombing resumed last year, but with dummy shells. Puerto Rico's new governor, Sila Calderon, who took office last month, campaigned on an anti-navy platform and tried to persuade Mr Clinton in the last days of he presidency to halt the bombing for good.
Ms Calderon has threatened to remove Puerto Rican guards from the entrance to the firing range and to hold an earlier, rival referendum. She says the bombing noise has produced an usually high rate of heart disease.
© Guardian Newspapers Limited 2001