() Some protesters demonstrating outside Immigration and Customs Enforcement buildings in Portland, Oregon, and suburban Chicago say they’re trying to deescalate tension through the visually striking use of inflatable costumes.

In recent days, observers in Portland have been treated to the bizarre sight of federal authorities in riot gear squaring off against Pikachu, SpongeBob SquarePants, bipedal frogs, extraterrestrials and other whimsical characters. Some images have gone viral.

“Operation Inflation” organizer Brooks Brown says the idea is to use humor to show that Portland hasn’t devolved into chaos and violence, as critics claim.

“It deflates. It switches the situation, and it changes the conversation to be what it should be, which is: What are people here protesting about? They’re protesting what ICE is doing, how ICE is doing it, and how they’re handling it what’s now happening to actual citizens,” he told over the weekend. “Instead of worrying about antifa and other stupid crap, let’s actually talk about this and have that conversation.”

Brown gestured at a handful of protesters that he said were “blowing bubbles and having pizza.” But by Sunday evening, hundreds of demonstrators thronged the ICE facility in rainy conditions (an added element this night: naked bicyclists), and authorities fired crowd-control munitions and made several arrests.

In Broadview, Illinois, west of Chicago, there have been similar clashes between protesters and federal agents, although state and local police have recently imposed controls on demonstrators, cordoning them back from the ICE detention center there. President Trump has sought to federalize and deploy National Guard troops in Chicago and Portland but has been legally checked in federal courts, at least temporarily.

On Sunday, inflatable costumes began materializing in Broadview. Characters loping into the protest zone included Cookie Monster, Winnie the Pooh, and a bumble bee holding a sign that said, “Bee benevolent, bee beautiful, bee better.”

correspondent Mills Hayes and producer Travis Harrison contributed to this report.