Facebook has discovered an Iranian-backed disinformation campaign attempting to stoke political and racial discord ahead of the U.S. midterm elections, the company said.

The company removed 82 pages and accounts on Facebook and Instagram that were part of a coordinated effort to fan tensions around politically charged topics such as race relations, opposition to the president and immigration. One of these pages had attracted at least million followers, Facebook said in a blog post.

An example of the racially charged content posted by Iranian groups
Facebook

“Despite attempts to hide their true identities, a manual review of these accounts linked their activity to Iran,” wrote Nathaniel Gleicher, Facebook’s head of cyber security. “We also identified some overlap with the Iranian accounts and Pages we removed in August.”

Facebook said it first detected this activity a week ago and, upon completing its initial investigation, immediately took action because of the approaching elections in the U.S. It also notified U.S. law enforcement, Congress and other technology companies.

Gleicher said some of the pages it removed had overlap with those taken down in August, though it too early to establish whether there are ties to the Iranian government. Tensions between the Washington and Tehran have been escalating as the Trump Administration withdrew from the 2015 nuclear deal with Iran and threatening stepped-up U.S. sanctions.

Facebook credited the work of its election “war room,” where more than 300 people across the company are working on safeguarding elections. The group is dedicated to rooting out disinformation, monitoring fake news and deleting fake accounts.