A massive cache of secret U.S. field reports from the Iraq war provides grim new details about the toll of that conflict, indicating that more than 100,000 Iraqis were killed during a six-year stretch and that American forces often failed to intervene as the U.S.-backed government brutalized detainees, according to news organizations given access to the documents by the WikiLeaks Web site.

The nearly 400,000 records are described as offering a chilling, pointillist view of the war's peak years, documenting thousands of civilian deaths - including hundreds killed at checkpoints manned by U.S. soldiers - and the burgeoning role that American contractors came to play in the conflict.

But the logs are perhaps most disturbing in their portrayal of the Iraqi government that has taken control of security in the country as U.S. forces withdraw.

The documents, including some dated as recently as 2009, report the deaths of at least six detainees in Iraqi custody because of abuse, and cite hundreds of other cases in which prisoners were subjected to electric shock, sodomized, burned, whipped or beaten by Iraqi authorities, according to an account in the Guardian, a British newspaper that was among several news organizations given advance access to the logs.

The others included the New York Times, the Qatar-based al-Jazeera satellite television network, Germany's Der Spiegel magazine, the French newspaper Le Monde and the Channel 4 news program in Britain. WikiLeaks, an anti-secrecy group that uses servers in several countries, published the records on its Web site (WikiLeaks.org) Friday evening.

There appear to be no major revelations in the latest logs. Much like those WikiLeaks released earlier this year on the war in Afghanistan, the Iraq documents are mainly low-level field reports that reflect a soldier's-eye view of the conflict but do not contain the most sensitive secrets held by U.S. forces or intelligence agencies.

The Pentagon condemned the release but did not question the authenticity of the files.

"We deplore WikiLeaks for inducing individuals to break the law, leak classified documents and then cavalierly share that secret information with the world, including our enemies," said Pentagon spokesman Geoff Morrell. He said the military would not comment on the information contained in the records but stressed that the "reports are initial, raw observations by tactical units. They are essentially snapshots of events, both tragic and mundane, and do not tell the whole story."

Even so, the spilling of so many once-secret files into public view allows for a fine-grained examination of the war. The 391,832 files included in the release cover a period from the beginning of 2004 to the end of 2009, and are more than quadruple the number of records that WikiLeaks published on the war in Afghanistan.

WikiLeaks has not disclosed the source of the materials. But suspicion has centered on Pfc. Bradley Manning, 22, an Army intelligence analyst whom the military arrested this year, charging him with the downloading and transfer of classified material.

Although narrow in nature, the records provide new insights into the toll of the conflict. According to al-Jazeera, the documents show that the U.S. military kept a tally of Iraqi casualties, even while insisting that such statistics were not maintained.

The files indicate that 285,000 casualties were recorded, including at least 109,032 violent deaths, although reports suggested some double-counting. Of those, 66,081 were civilians, 23,984 were "enemy," 15,196 were members of the Iraqi security forces, and 3,771 were U.S. and allied service members.