Peter Lee, who worked for defence contractor TRW Inc which the Pentagon had hired, and was assigned to a classified Pentagon project, divulged the secrets of submarine detection technology in a two-hour lecture he gave in Beijing in may 1997, the paper said in a front page report.

The technology, a crucial military advantage, was zealously guarded by Pentagon for the navy's ability to conceal its submarines, it said, adding, the secrets were considered promising and had been developed for two decades.

Federal prosecutors in Los Angeles wanted to charge Lee with espionage but were held back partly because navy officials in Washington did not permit testimony about the technology in open court, the paper saidquoting law enforcement officials.

The justice department in Washington, having some questions of its own, would not approve the prosecution either, the officials said.

Instead, Lee ended up pleading guilty to filing a false statement about his trip to China and to divulging classified laser data to Chinese scientists during an earlier trip to China in 1985.

Peter Lee is not related to Won Ho Lee, another Chinese American scientist, who is suspected to have revealed American nuclear secrets to China.

Despite failure to prosecute Lee over radar technology, the Times said the case showed that the scope of Chinese espionage was broader than the assertions of nuclear thefts at Los Alamos national laboratory.

The submarine technology was developed at Lawrence Livermore national laboratory in California.

The Peter Lee case is also considered significant because it clearly demonstrates that American government beleived that China was successfully engaged in espionage -- obtaining American defencedata -- during president Bill Clinton's second term, the paper said.

The technology at issue involved a radar ocean imaging programme developed in cooperation with Britain.

Former manager of the programme Richard Twogood was quoted as saying becasue the project was still in developmental stage, there was debate in the government over its significance.

Analysts considered it as vital to American national security since submarine and anti-submarine warfare are crucial to the defence of the United States, but others were uncertain about how useful the technology would be, he said.

The technology seeks to detect the physical traces, briefly left as signatures on water surfaces, of undersea motions of submarines. Remote sensing devices located, for example, in aeroplane pick up the traces.

``The navy has invested a lot in this area for twenty years or so by definition that implies it's important,'' Twogood said.

The Soviet Union worked hard to develop this technology during the Cold War. Americanadvances suggested that the Soviet assertion in anti-submarine measures should be taken more seriously, he added.