On Feb. 27, an article claiming that the United States was behind the bombing of the Nord Stream underwater pipelines in the Baltic Sea was published on the Substack and Blogspot blogging platforms.

Within 24 hours, the article — and other versions of it — had been posted to more websites, including Reddit, Medium, Tumblr, Facebook and YouTube. Translations of the article in Greek, German, Russian, Italian and Turkish also began appearing online.

The posts were part of a Chinese influence campaign that stands out as the largest such operation to date, researchers at Meta said in a report on Tuesday. The effort, which the company said had started with Chinese law enforcement and was discovered in 2019, was aimed at advancing China’s interests and discrediting its adversaries, such as the United States, Meta said.

In total, 7,704 Facebook accounts, 954 Facebook pages, 15 Facebook groups and 15 Instagram accounts tied to the Chinese campaign were removed by Meta, which owns Facebook, Instagram and WhatsApp. Hundreds of other accounts on TikTok, X, LiveJournal and Blogspot also participated in the campaign, which researchers named Spamouflage, for the frequent posting of spamlike messages, according to Meta’s report.