Facebook parent company Meta (META.O) said on Tuesday it had uncovered links between people associated with Chinese law enforcement and a long-running but largely ineffectual operation to positively influence people on social media about China.

The social media giant removed around 7,700 Facebook accounts and hundreds of other pages, groups and Instagram accounts connected to the so-called "Spamouflage" campaign, elements of which have been active since 2018, it said in a quarterly security report.

The "Spamouflage" network has engaged in spurts of activity over the last several years pushing positive narratives about China and negative commentary about the United States, Western foreign policies and critics of the Chinese government.

With the latest activity detected, Meta executives said they believed that "Spamouflage" had become the largest known cross-platform influence operation to date, with a presence on at least 50 services.

Clusters of the campaign's fake accounts were run from different parts of China, but shared digital infrastructure and appeared to operate with clear shift patterns, including breaks for lunch and dinner on Beijing time, Meta said.