One journalist's bid to report mass murder in South Korea in 1950 was blocked by his British publisher. Another correspondent was denounced as a possibly treasonous fabricator when he did report it. In South Korea, down the generations, fear silenced those who knew.

Fifty-eight years ago, at the outbreak of the Korean War, South Korean authorities secretively executed, usually without legal process, tens of thousands of southern leftists and others rightly or wrongly identified as sympathizers. Today a government Truth and Reconciliation Commission is working to dig up the facts, and the remains of victims.

How could such a bloodbath have been hidden from history?

Among the Koreans who witnessed, took part in or lost family members to the mass killings, the events were hardly hidden, but they became a "public secret," barely whispered about through four decades of right-wing dictatorship here.

"The family couldn't talk about it, or we'd be stigmatized as leftists," said Kim Chong-hyun, 70, leader of an organization of families seeking redress for their loved ones' deaths in 1950.

Kim, whose father was shot and buried in a mass grave outside the central city of Daejeon, noted that in 1960-61, a one-year democratic interlude in South Korea, family groups began investigating wartime atrocities. But a military coup closed that window, and "the leaders of those organizations were arrested and punished."

Then, "from 1961 to 1988, nobody could challenge the regime, to try again to reveal these hidden truths," said Park Myung-lim of Seoul's Yonsei University, a leading Korean War historian. As a doctoral student in the late 1980s, when South Korea was moving toward democracy, Park was among the few scholars to begin researching the mass killings. He was regularly harassed by the police.

Scattered reports of the killings did emerge in 1950 _ and some did not.

British journalist James Cameron wrote about mass prisoner shootings in the South Korean port city of Busan _ then spelled Pusan _ for London's Picture Post magazine in the fall of 1950, but publisher Edward Hulton ordered the story removed at the last minute.

Earlier, correspondent Alan Winnington reported on the shooting of thousands of prisoners at Daejeon in the British communist newspaper The Daily Worker, only to have his reporting denounced by the U.S. Embassy in London as an "atrocity fabrication." The British Cabinet then briefly considered laying treason charges against Winnington, historian Jon Halliday has written.

Associated Press correspondent O.H.P. King reported on the shooting of 60 political prisoners in Suwon, south of Seoul, and wrote in a later memoir he was "shocked that American officers were unconcerned" by questions he raised about due process for the detainees.

Some U.S. officers _ and U.S. diplomats _ were among others who reported on the killings. But their classified reports were kept secret for decades.