American officials see the activity on Facebook as relatively minor so far. China, according to two American officials, has not yet decided whether to try to influence the election in November in any substantial way.
Microsoft has also reported observing Chinese activity aimed at gathering information about the presidential campaign. Last week, the company reported efforts by China to hack into Mr. Biden’s campaign and American think tanks. American intelligence officials have said that China may have been looking for opposition research critical of Mr. Trump, and the targeting of Mr. Biden’s campaign does not undermine the government’s assessment that China opposes Mr. Trump.
Facebook also briefed Congress before its announcement on Tuesday. William R. Evanina, the senior intelligence official in charge of foreign election threats, was set to brief the congressional intelligence committees in the next few days on the latest findings of election influence and interference operations.
The network discovered by Facebook included 155 accounts, 11 pages, nine groups and six Instagram accounts. Posting in Chinese, Filipino and English, the group largely pushed stories of interest to overseas Filipino workers, as well as content that was supportive of President Rodrigo Duterte’s campaign for re-election in the Philippines.
Facebook also announced the removal of a coordinated campaign operating on behalf of a government entity in the Philippines. That campaign, which included 57 Facebook accounts, 31 pages and 20 Instagram accounts, was followed by about 276,000 people, largely in the Philippines.
“Although the people behind this activity attempted to conceal their identities, our investigation found links to Philippine military and Philippine police,” Facebook wrote in its report. The activity was brought to their attention by civil society groups and Rappler, an independent news organization in the Philippines that the Duterte government has targeted.
Adam Goldman and Julian E. Barnes reported from Washington, and Sheera Frenkel from Oakland, Calif.