Two weeks after Facebook expunged a supposedly independent news site linked to Russia’s military intelligence arm, the banned site is smuggling its Putin-friendly content back into the social network’s streams by using a Moscow publisher as a cut-out, the Daily Beast has found.

The cat-and-mouse game between the Silicon Valley giant and those alleged to be covert officers in Russia’s Main Intelligence Directorate, or GRU, illustrates the challenges ahead of Facebook, which deployed COO Sheryl Sandberg to face a new round of grilling Wednesday from Senate lawmakers probing foreign interference operations on the site.

“Facebook is now going after malicious actors fairly well, finding people who are not who they say they are,” said Clint Watts, a research fellow at the Foreign Policy Research Institute. “But those actors are just going to continue to go at it, and they’re going to change their approach.”

Facebook announced August 21 that it removed a new batch of fake accounts and pages connected to Russia. Unlike the company’s previous efforts against the privately-operated Internet Research Agency, the latest round of house-cleaning targeted accounts linked “to sources the US government has previously identified as Russian military intelligence services,” according to Facebook.

One of those banned pages—and the only one Facebook would name publicly—is the “Inside Syria Media Center” (ISMC), which has faced previous accusations of fabricating news stories and inventing reporters while pushing the Kremlin’s favored narratives on the crisis in Syria.

But even though the ISMC’s Facebook page is gone, ISMC’s content still has a path to Facebook through other outlets not subject to the ban.

In announcing its removal of the Kremlin-linked accounts last month, Facebook said it hadn’t “found activity by these accounts targeting the U.S.” But the ISMC first came to public attention last year through its aggressive efforts to place bylined English-language stories with U.S. publications.

One outlet, the California-based lefty news site Counterpunch, reported receiving freelance pitches “two or three times a week” for over a year from a single ISMC staffer called “Sophia Mangal” and “Sophie Mangal.”

Mangal is listed on the ISMC’s website as co-editor, and her byline can be found on more than a dozen other sites, with her ISMC affiliation listed in her bio or the ISMC cited in the story text. “The crux of her works read like regime-sponsored press releases,” Counterpunch wrote. “Virtually all exalted Russia’s military prowess and the tenacity of the Assad regime, as if she was embedded within the Syrian Army.”

Counterpunch became suspicious of Mangal while investigating another ersatz freelance writer called Alice Donovan, who duped Counterpunch into publishing five articles, despite not being a real person. Last December, citing confidential FBI reports, the Washington Post identified Donovan as a Kremlin persona. And in June, Robert Mueller’s election interference indictment against 12 GRU officers listed Alice Donovan as one of the fake identities used by the GRU’s Unit 74455. The Donovan Facebook profile—since deleted—was even used to set up a Facebook page for DC Leaks, according to Mueller, a fake whistleblower site used to release some of the emails stolen by the GRU’s hackers.

Counterpunch reporters found that Donovan’s stories were often nearly word-for-word matches with those attributed to Mangal and other supposed ISMC reporters. There were other warning signs as well. Though she writes in broken English, the most detailed version of Mangal’s bio has her as a 27-year-old former media and journalism major at the University of North Carolina at Chapel Hill. On her Linkedin profile Mangal describes herself as “an American Patriot, a special investigative writer, and a contributor.”

After an extensive investigation, Counterpunch could find no evidence proving that Mangal, or any of the other names affiliated with ISMC, actually exists. (The Daily Beast reached out to the email addresses for Mangal and the ISMC, but received no response.)

Real or not, Mangal and her ISCM colleagues are back on Facebook despite the ban, courtesy of a Russian website called Oriental Review. The site appears to have first published Mangal’s byline last November. Her contributions include a story in April claiming the British government was “trying to cover up the tracks and destroy all the evidence” in the nerve agent poisoning of GRU defector Sergei Skripal, a conspiracy theory heavily promoted online by the Russian government.

The most recent article appeared on the site last week, as the Syrian military massed for an assault in Idlib against the rebel groups opposing Syrian strongman Bashar al-Assad. “[It] will be extremely difficult to resist the battle-hardened Assad’s Government army.” The piece promptly appeared on Oriental Review’s Facebook page, which has 6,000 followers, and on the page of at least one other site that syndicates Oriental Review’s content.

Oriental Review has no readily-apparent ties to the Russian government, though it shares ISCM’s pro-Kremlin, anti-U.S. viewpoint, and holds a tight focus on Western readership. All of its content is published in English, and its Russian origin is largely unadvertised. Some time between January and March of this year, according to archives, Oriental Review changed the description on its about page, which originally described the site as “an independent Moscow-based Internet journal.” The text now reads, “an international e- journal” with no mention of Russia or Moscow.

The site was founded in 2010 by a Moscow man named Andre Fomine, according to posts on the site and Fomine’s social media accounts. (Fomine did not respond to an email from the Daily Beast). One early article bearing Fomine’s byline was headlined “US State Department Defends Russian Sodomites.” Like other sites that have published ISCM content, Oriental Review also accepts outside submissions, and some 20 different bylines now grace its masthead of “top contributors,” including Mangal.

It’s unclear whether other alleged Russian front organizations have returned to Facebook through cut-outs, because Facebook has so far refused to name the other banned accounts and pages. “We don’t have any updates to offer,” said spokesman Tom Reynolds in an email Tuesday. But the company’s current approach to the problem may not suffice, said Watts, a former FBI agent who’s studied Russia’s active measures.

“The problem hasn’t been resolved,” Watts said. “They’ve never dealt with the veracity of the information on the platform.”

Facebook’s focus has been on rooting out inauthentic identities, a solution that doesn’t work against an adversary with access to dozens of obscure or fringe websites operated by real people. Sooner or later, Facebook will have to target the underlying content instead, said Watts.

“The question comes down to, What are you going to do about fake news?”