“FAKE NEWS — A TOTAL POLITICAL WITCH HUNT!” the president-elect wrote in a message on Twitter.

[Click following link to access the full 35-page report.]

BuzzFeed News became the center of a swirling debate over journalistic ethics on Tuesday after its decision to publish a 35-page document carrying explosive, but unverified, allegations about ties between the Russian government and President-elect Donald Trump.

The document, a dossier prepared by a former British intelligence officer hired by Mr. Trump’s political opponents, had been circulating among high-ranking politicians and some journalists since the fall. Intelligence officials recently presented a 2-page summary of the allegations to Mr. Trump and President Obama, CNN reported on Tuesday.

But CNN declined to include the specific allegations contained in the dossier - such as collusion between Mr. Trump’s team and Russian operatives - saying that its journalists could not independently verify them.

Roughly an hour later, BuzzFeed, in a break from typical journalistic practice, posted the document that fully detailed the unverified allegations to which CNN had alluded.

“BuzzFeed News is publishing the full document so that Americans can make up their own minds about allegations about the president-elect that have circulated at the highest levels of the US government,” BuzzFeed wrote.

Ben Smith, BuzzFeed’s editor in chief, declined to comment beyond the article, which carried the bylines of three BuzzFeed reporters. But in a memo to his staff, Mr. Smith offered a further explanation about why the site had published the document.

“Our presumption is to be transparent in our journalism and to share what we have with our readers,” Mr. Smith wrote. “We have always erred on the side of publishing. In this case, the document was in wide circulation at the highest levels of American government and media.

“Publishing this document was not an easy or simple call, and people of good will may disagree with our choice,” Mr. Smith added. “But publishing this dossier reflects how we see the job of reporters in 2017.”

CNN said that its journalists had reviewed the full 35-page compilation of memos, the same document later published in full by BuzzFeed, but declined to include some details, saying that the network “has not independently corroborated the specific allegations.” CNN said its reporters spoke with multiple high-ranking intelligence and government officials before publishing its report.

On social media, some left-leaning writers who generally oppose Mr. Trump expressed skepticism about the document published by BuzzFeed. “An anonymous person, claiming to be an ex-British intel agent & working as a Dem oppo researcher, said anonymous people told him things,” wrote Glenn Greenwald, the journalist who was instrumental in publishing Edward Snowden’s leaks about government surveillance.

Mr. Trump, for his part, seized on the report on Tuesday evening to denigrate the news media and his detractors. “FAKE NEWS — A TOTAL POLITICAL WITCH HUNT!” the president-elect wrote in a message on Twitter.