The Justice Department is investigating possible criminal activity linked to millions of fake or duplicated messages — many from Russian email addresses — sent to the Federal Communications Commission opposing net neutrality, Buzzfeed reported Saturday.

Of the 22 million messages sent last year to the FCC website, nearly 21 million were bots, organized campaigns or fakes, including many using stolen identities, according to a Stanford University study. Some campaigns also involved fake, automated comments, though others were legitimate. Talk show host John Oliver notably encouraged viewers to back net neutrality, triggering a deluge of comments that the FCC falsely claimed helped trigger a shutdown of its website, according to the study.

Of the total estimated 800,000 unique comments sent, 99.7 percent supported net neutrality and opposed a controversial push by the Trump administration’s commission head Ajit Pai to terminate net neutrality. Pai recently admitted that Russia meddled in the system and acknowledged that 500,000 of the suspect comments were linked to Russian emails.

The FBI subpoenaed at least two organizations for information linked to the messages just days after New York state did so for details from 14 groups in October for its own probe, sources told Buzzfeed. Massachusetts and the District of Columbia are supporting the New York probe, Buzzfeed reported.

The FCC was inundated with the fake comments as the commission debated dumping net neutrality, which had barred all internet service providers from blocking, slowing down, or charging extra for certain content.

Net neutrality is hugely popular with the American public, according to several polls. The FCC voted late last year to terminate it, which paves the way for corporations to sharply increase consumer rates if users want to maintain the same internet speed for all content.