Facebook trumpeted on Tuesday the deletion of hundreds of pages and accounts run by the Internet Research Agency, the Kremlin-linked troll army that has sought to meddle in U.S. politics. But of the five examples of deleted accounts Facebook provided the public, CNN has found, two had links to the troll army that should have been obvious to the social networking company months ago.
In November, the House Intelligence Committee released a list of almost 3,000 Twitter accounts that Twitter had determined were run by the Internet Research Agency.
Among the five examples of shuttered accounts Facebook provided in its blog post announcing the move on Tuesday were the pages "RU Open" and "Politkach." The Twitter accounts associated with both of these pages were included in the list published by the House Intelligence Committee in November -- five months before the Facebook accounts were deleted. A YouTube account associated with RU Open remained active until Wednesday, when CNN asked YouTube about it.
CNN determined the Twitter accounts were associated with both of the Facebook pages by examining cached data which showed the pages had the same branding and linked back to the same websites.
"It's not like we discovered all of these accounts on Tuesday morning," Nathaniel Gleicher, Facebook's head of cybersecurity policy, told CNN on Wednesday. Facebook would not say when it first learned about individual accounts.
Gleicher said Facebook has continued investigating the troll group's activity since last year, when Facebook removed hundreds of pages and accounts the group controlled that were designed to look like they were run by real American activists.
Explaining why Facebook removed all 300 of the accounts and pages at once on Tuesday, Gleicher said that if the company were to remove each individual page as its ties to the Internet Research Agency were confirmed, it would risk tipping off the troll group off and giving it a chance to try to obscure its connection to other accounts it might be running.
In February, Special Counsel Robert Mueller's office indicted 13 Russian nationals who allegedly had links to the troll group.
"It's really a fundamental problem that you face across law enforcement and that you face in the technical sector," Gleicher said of the decision to remove the accounts in batches rather than one-by-one. "There's not obvious answer in all cases but the goal is to be most impactful, to have the greatest reduction of malicious actors and the least risk of impacting innocent users."
Related: Facebook finds hundreds more accounts run by Kremlin-linked troll group
Facebook, Twitter and YouTube coordinate to curb the spread of terrorist content online through the Global Internet Forum to Counter Terrorism, but it is not clear if a similar partnership is in place for government-linked propaganda like the Russian troll operation.
Gleicher said Facebook is in regular communication with other platforms like Twitter and YouTube on this issue. He would not detail what information the companies share with each other, citing the sensitive nature of such investigations.
On Tuesday morning, Facebook said it had removed 138 Facebook pages, 70 Facebook profiles, and 65 Instagram accounts it determined were linked to the troll group. The pages, which were followed by more than one million users, were mainly aimed at Russian speakers around the world, Facebook said, including in Russia itself and neighboring countries Azerbaijan, Uzbekistan and Ukraine.
The company said that it removed the pages and accounts because of their links to the Internet Research Agency, and not based on the content they were sharing. Facebook suggested that some of the pages shared mostly innocuous content.
Asked by CNN, Twitter and YouTube would not comment on whether they had the same blanket ban on the Internet Research Agency.
A YouTube account associated with one of the accounts Facebook shuttered on Tuesday was still live on YouTube on Wednesday morning. The account included videos of Crimeans saying they were happy with Russian control of the region.
One of the videos that was live until CNN contacted YouTube on Wednesday, was published a few days after the Trump administration announced sanctions against Russia for election meddling, RU Open asked people in Crimea for their response to the move.
"What would you like to say to Western politicians that stand against Russia?" they asked one woman. "The heck with them," she responded. "Our president is the best, he's the most intelligent and talented."
The account appeared to have been removed by YouTube on Wednesday afternoon. The company declined to comment.