WhatsApp has always claimed that its messages are end-to-end encrypted, ensuring that no one else but you and the recipient of the messages can see it. Facebook’s CEO Mark Zuckerberg had even claimed in front of the U.S. Senate in 2018 that the company does not see any WhatsApp content. However, a troubling new report suggests that might not be true.

The ProPublica report claims that WhatsApp has over 1,000 contract workers in Austin, Texas, Dublin, and Singapore office buildings. These contract workers go through private messages and media files reported by WhatsApp users and scanned by the company’s AI system.

Since WhatsApp messages are end-to-end encrypted, they cannot be read by AI systems. This is why when a WhatsApp user reports a message; five messages are forwarded — the offending message along with four previous ones to a ticketing system from where it is assigned to a contract worker.

These contractors pass judgment on whatever flashes on their screen — claims of everything from fraud or spam to child porn and potential terrorist plotting — typically in less than a minute.

These contract workers are paid hourly and use special software designed by Facebook to go through the messages.

Carl Woog, the Director of Communications at WhatsApp, confirmed to Pro Publica that contract workers review WhatsApp messages to remove “the worst” abusers but that it does not consider this content moderation. “We actually don’t typically use the term for WhatsApp,” he said.

The report further alleges that since Facebook purchased WhatsApp, it has taken several actions which have compromised its security and privacy. This includes extensive use of outside contractors from WhatsApp, AI systems, and more, which examine user messages and media files.

WhatsApp user data, ProPublica has learned, helped prosecutors build a high-profile case against a Treasury Department employee who leaked confidential documents to BuzzFeed News that exposed how dirty money flows through U.S. banks.

The condition under which moderators work and are hired has also been detailed. They are paid $16.50 per hour by Accenture, one of the top corporate contractors. The job listings are only published for “Content Review” positions, with no mention of WhatsApp or Facebook. The content moderators are required to sign strict NDAs. They handle up to 600 “tickets” each day.

Facebook has declined to comment on the report, though given the bad publicity that it will garner now, that should change sometime soon.