LONDON, Jan 11 (AFP) - Thousands of Britons living close to depleted uranium (DU) firing ranges or factories producing the munitions are at risk from contamination, an expert warned on Thursday.

Meanwhile, media reports said that Britain's defence ministry has been aware for almost four years that soldiers exposed to DU munitions risked developing cancer.

Professor Malcolm Hooper, from Sunderland University, north-east England, said there was a "very real" danger to people living near centres manufacturing DU projectiles.

"Often these are covert and are not known to the local population," he said in a news interview with the private ITV channel.

Hooper, who has given evidence on depleted uranium to the British parliament's Defence Select Committee, said: "It will be people living near firing ranges (who are at risk) although these are usually located in more remote areas."

His comments come after the government on Tuesday announced a voluntary screening programme for troops who had served in the Balkans conflict who fear that contact with depleted uranium has put their health at risk.

But the government stressed it did not believe there was any danger.

The offer of tests to soldiers has failed to satisfy veterans' groups, which complained the government had not gone far enough in addressing their concerns.

Newspapers and broadcasters reported Thursday that Britain's defence ministry had been aware of potential risks from depleted uranium since at least April 1997.

The BBC said that a report from the headquarters of the Army's Quartermaster-General had warned that soldiers dealing with vehicles which had been hit by DU-tipped projectiles would be exposed to up to eight times the acceptable level of exposure to uranium, unless they were provided with respiratory equipment.

But the defence ministry dismissed the report as a "discredited" draft paper, saying it had been prepared by a trainee and had not been endorsed by more senior staff.

Iain Duncan Smith, defence spokesman for the opposition Conservative party, said: "If they are claiming that the evidence in this document was flawed, they should now release the new evidence that disproved it."

Battlefield munitions are often tipped with depleted uranium, an extremely dense substance which allows them to penetrate tank armour.

The current scare over DU shells centres on their use by US bombers in Bosnia and Kosovo.

Italy claims that a number of its troops are suffering from leukemia, possibly as a result of exposure to spent DU shells while on peacekeeping duty in the Balkans.

Other countries, including Germany, Belgium and Portugal have put pressure on NATO chiefs to look again at the use of DU munitions by the forces under their command.