A St. Mary Parish chemical plant was among the targets of a shadowy Russian group that spreads disinformation on the Internet, according to The New York Times.

The highly coordinated Sept. 11 hoax involved a non-existent explosion and toxic fume release, reported via dozens of fake Twitter accounts posting hundreds of tweets for hours, according to the Times. The tweets targeted people chosen to generate maximum attention.

The culprit, according to the story, was the Internet Research Agency, based in St. Petersburg, Russia. The agency uses an army of “trolls” is to wreak havoc on the web and in American communities.

The hoaxers may have spent weeks on the project, creating fully functional clones of the websites of Louisiana TV stations and newspapers. They also created a Wikipedia page for the disaster. St. Mary Parish residents unwittingly contributed to the virtual assault, unfolded through text messages.

The story details how the pro-Kremlin propaganda agency has industrialized the art of trolling, posting deliberately inflammatory comments to create disruption and arguments. The article says Russia has undertaken the biggest trolling operation in history in an effort to derail the Internet as a democratic space.