The Federal Communications Commission says its web site was hit with an online attack Sunday night, about the same time HBO's John Oliver urged viewers to go to the site to post comments in support of current net neutrality regulations.

Multiple distributed denial of service attacks (DDoSs) began Sunday at midnight, FCC Chief Information Officer David Bray said in an announcement released Monday afternoon. "These were deliberate attempts by external actors to bombard the FCC’s comment system with a high amount of traffic to our commercial cloud host," he said. "These actors were not attempting to file comments themselves; rather they made it difficult for legitimate commenters to access and file with the FCC."

The FCC's comment system remained operational, Bray said, but the DDoS attacks "tied up the servers and prevented them from responding to people attempting to submit comments.  We have worked with our commercial partners to address this situation and will continue to monitor developments going forward.”

Three years ago, Oliver spurred a massive response after a segment on net neutrality on his show Last Week Tonight. After explaining the principle that the FCC was considering --Internet service providers (ISPs) should treat all legal content and applications equally and not block or slow content -- he encouraged fans to submit supportive comments on the agency's website. That caused the site to crash.

On his latest episode, which debuted Sunday night, Oliver urged viewers "once more into the breach."

The FCC had prepared for a new round of public comment after FCC Chairman Ajit Pai last month began the process of reconsidering the net neutrality rules, passed in 2015.

The timing just seems too coincidental, says Evan Greer, campaign director for Fight for the Future, a non-profit organization that supports free expression on the Net. Either there was a DDoS attack that prevented comments from being submitted or the agency could be "intentionally misleading" the public by blaming the attack, when the site was not fully prepared for the influx of comments, she said.

For transparency, the agency should release its logs to an independent security analyst to verify what happened, Greer says. “The FCC’s statement today raises a lot of questions," she said, "and the agency should act immediately to ensure that voices of the public are not being silenced as it considers a move that would affect every single person that uses the Internet."

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John Oliver sends fans to FCC site in one last plea for net neutrality

Follow USA TODAY reporter Mike Snider on Twitter: @MikeSnider.