Undercover videos caught anti-Trump activists discussing the possible means to disrupt an inaugural ball that will be held Thursday night at the National Press Club and the different ways to “shut down D.C.” on the inauguration day itself.

One of the videos was obtained by a journalist from Project Veritas who got invited to a meeting of D.C. Anti-Fascist Coalition, a group that is under the #DisruptJ20 organization. The #DisruptJ20, which is backed by “national support,” calls for “mass protests to shut down the inauguration of Donald Trump” and makes plans to ensure this objective is fulfilled.

In the video, four men—Luke Kuhm, Scott Green, Colin Dunn and Casey Webber—talked about the possible ways by which they could disrupt the DeploraBall, a black-tie Pro-Trump event that will be held the night before the inauguration. Luke Kuhm is known in online activist forums as “lukefromdc.” Scott Green was identified as one of the leaders of the D.C. Anti-Fascist Coalition.

They considered the use of butyric acid to create stink bombs.

“If you had a pint of butyric acid, I don’t care how big the building is, it is closing,” Kuhm said.

“And this stuff is very efficient, it’s very, very smelly, and it lasts a long time,” Green replied.

The group also talked about activating the sprinkler system or setting off the fire alarm in a way that “looks like an accident” to “ruin their evening” and “ruin their outfits” so the ball attendees would be forced to leave.

“And you add the benefit, everybody is going to walk outside in the freezing cold,” Dunn said.

Project Veritas has forwarded the video to the authorities. James O’Keefe, founder and president of Project Veritas, explained that holding peaceful protests practing one’s First Amendment rights is not against the law. However, plotting to shut down an event could be a criminal offense.

“But in this case, #DisruptJ20 says openly that their plan is to shut down the inauguration. The question is, where do these people draw the line?” he said.

The anti-Trump organization issued a statement Monday dismissing the video, saying the people in it knew someone in the group was a plant so they intentionally “gave him false information” and “false plans.”

“The group had no intention of causing any damage or disruption at the Deploraball,” the statement said.

Another undercover video, obtained Jan. 8 at a #DisruptJ20 Spokes Council meeting, shows #DisruptJ20 members planning to block all major entry points to D.C. on the day of Donald Trump’s inauguration. One strategy is to chain trains at Metro Center, Gallery Place and L’Enfant Plaza because “they are all close enough to walk to and that’s every single line in the city.”

In the video, #DisruptJ20 organizer Legba Carrefour described how they could chain the trains in about 15 seconds.

“So we figured out this, the trains pull up, one person is going to lock one end of a chain to an edge, and on the other end of the chain the end of the car…done. It takes 15 seconds and everyone can leave and literally it can’t go anywhere at that point, its anchored,” Carrefour said.

The group also planned to block traffic by setting up tables where they would give out food and other things to the poor and homeless to block the “vehicle traffic and the pedestrian traffic flowing in the inauguration.”