Last Updated 4:10 p.m. ET
More than a quarter-million U.S. State Department documents obtained by the whistle-blowing website WikiLeaks were leaked to The New York Times and other international news organizations, in defiance of demands by the U.S. government to stop the release.
The documents - communications between the State Department and its embassies and diplomats around the world - include candid assessments of foreign leaders and governments.
The White House, saying it endangers U.S. diplomats, intelligence agents and democratic activists who seek America's help.
The White House called the release "reckless and dangerous" and counter to President Barack Obama's goal of open and accountable government at home and around the world. It also said such initial reporting and directives found in the "stolen" documents is "often incomplete information" and doesn't always shape final policy decisions.
By mid-Sunday afternoon, the leaked documents appeared on the websites of the New York Times, the Guardian (U.K.), Spain's El Pais, France's Le Monde, and in a preview article on the site of the German magazine Der Spiegel.
CBS News correspondent Ines Ferre reports some reveal that Saudi donors remain chief financiers of militant groups like al Qaeda, and that Chinese government operatives have waged a coordinated campaign of computer sabotage targeting the United States and its allies.
The group's founder, Julian Assange, told the U.S. ambassador to Britain that WikiLeaks would not bow to Washington's demands.
The WikiLeaks website appeared to be inaccessible, and WikiLeaks said in its Twitter feed that it was experiencing a denial of service attack.
WikiLeaks said that publications in the U.S. and Europe would print the leaked diplomatic cables even if it could not.
Cables Shine Light Into Secret Diplomatic Channels (NYT)
The US Embassy Cable (Guardian)
A Superpower's View of the World (Spiegel, in English)
Los papeles del Departamento de Estado (El Pais)
Wikileaks: Dans les coulisses de la diplomatie américaine (Le Monde)
The Obama administration has been bracing for the release for the past week. Top officials have notified allies that the contents of the diplomatic cables could prove embarrassing because they contain candid assessments of foreign leaders and their governments, as well as details of American policy.
Lawrence Korb, senior fellow at the Center for American Progress, told CBS News the release will compromise future information sent by embassies to the State Department.
"It makes it much for difficult for the United States to protect its interests in the international system, if the leaders in Washington can't get access to very honest advice," Kolb said.
The Times writes that most of the cables date from the past three years, with some as recent as February.
In an online article previewing the magazine's Monday publication of the cables, Der Spiegel wrote that the WikiLeaks release represents 243,270 diplomatic cables filed by American embassies to the State Department, and 8,017 directives that the State Department sent to its diplomatic outposts around the world.
According to The Times, none of the cables provided to it were marked "Top Secret." Approximately 11,000 were marked "Secret."
Nine thousand were labeled "NOFORN" (NOT TO BE SHARED WITH ANY FOREIGN GOV'T).
"Never before in history has a superpower lost control of such vast amounts of such sensitive information - data that can help paint a picture of the foundation upon which US foreign policy is built," the editors wrote. "Never before has the trust America's partners have in the country been as badly shaken."
CBS News correspondent Cami McCormick reports that some of the cables disclose diplomatic communications between U.S. and South Korean officials on the North's economic troubles; and bargaining with other countries to empty the Guantanamo Bay prison of terror detainees.
Shortly before, WikiLeaks said its website was "currently under a mass distributed denial of service attack."
There was no way to immediately confirm the cyberattack, although the WikiLeaks website was not available online.
The State Department's top lawyer warned Assange late Saturday that lives and military operations would be put at risk if the cables were released. Legal adviser Harold Koh said WikiLeaks would be breaking the law if it went ahead and he also rejected a request from Assange to cooperate in removing sensitive details from the documents.
Assange, in a response released Sunday by his London lawyer, said he had no intention of halting the release. He claimed the administration was trying to cover up alleged evidence of serious "human rights abuse and other criminal behavior" by the U.S. government.
The letter to the U.S. ambassador, Louis Sussman, also said WikiLeaks had no desire to harm either "individual persons" or "the national security of the United States." But he said the administration's refusal to cooperate showed that the risks were "fanciful."
"I understand that the United States government would prefer not to have the information that will be published in the public domain and is not in favor of openness," Assange wrote. "That said, either there is a risk or there is not."
"You have chosen to respond in a manner which leads me to conclude that the supposed risks are entirely fanciful and you are instead concerned to suppress evidence of human rights abuse and other criminal behavior," he said.
"We will now proceed to release the material subject to our checks and the checks of our media partners unless you get back to me," Assange wrote.