The sound of honking horns reverberated off the walls as dozens of cars slowly circled City Hall on Monday afternoon, with signs reading “Inaction=Murder” and “Jail the Virus — Free Our People” taped to their tightly shut windows.

This demonstration — a call to reduce the population of Philadelphia jails and state prisons, where officials have confirmed that prisoners and staff have tested positive for the coronavirus — was one indication that even under Gov. Tom Wolf’s stay-at-home order, Philadelphians will find new ways to take their demands to the streets.

In cities around the world, under similar lockdowns, car caravans have quickly emerged as one means of mobilizing within the strictures of social distancing.

Here in Philadelphia, Refuse Fascism has planned a “Drive Trump/Pence Out Now!" caravan to roll through West Philadelphia this weekend. Advocates have also toyed with such a procession to amplify demands for the seizure of Hahnemann University Hospital by eminent domain to house COVID-19 patients. So far they’ve opted for a "call-in day and social media storm” instead. And in New Jersey, a hundred cars lined up to demand the release of immigrants in the Hudson County ICE Detention Center.

» READ MORE: Mayor Kenney accuses Hahnemann owner of ‘trying to make a buck’ on the coronavirus

Monday’s demonstration — timed to generate a din during Mayor Jim Kenney’s afternoon news briefing, and seen on Twitter and Facebook Live — was the culmination of a campaign that has been waged over several weeks on Twitter and Facebook, through email and phone banks, and, as of Monday, in a lawsuit filed by the ACLU of Pennsylvania seeking action from the state Supreme Court.

“At this time when we’re all trying to keep ourselves safe, for people who are elderly and immunocompromised especially, jail is the least safe place to be right now,” said John Bergen, an associate pastor at Germantown Mennonite Church.

» READ MORE: Amid coronavirus threat, Philadelphia will follow New Jersey and New York City in a push to cut the jail population

He said gathering for the car caravan felt more satisfying than all those distant digital pleas cast out over social media. He hoped it would be effective, too.

“I think the thing that so many of us have been missing the last few weeks is the ability to gather and hear each others’ voices not through a Zoom line or a phone call,” he said. “There’s a real joy I’m experiencing right now, in being able to circle City Hall and hear each other’s horns and see each other’s faces. I’m seeing them through their car windows, but we’re all able to make noise and shout together. I feel powerful right now.”

The fallout from the coronavirus has energized people to step up at an unprecedented level, according to Paul Engler, who co-founded an organization that trains activists and co-authored a book on mass mobilization, This Is an Uprising: How Nonviolent Revolt Is Shaping the Twenty-First Century.

» READ MORE: Why Philly workers are fighting for a local coronavirus relief fund

There are massive amounts of people who are activated outside of traditional organizational structures that want to participate in the solution,” he said. At the same time, organizers “can’t use the same mechanisms they’ve always used to engage people in activism and in mutual aid.”

They’re finding new ways, though: There are massive phone banks to simultaneously offer help and sign on supporters. Workers at Amazon and Instacart have walked off the job to demand safety measures. And there’s the nationwide #SolidarityAt8 campaign to applaud health-care workers each night at 8 p.m. with a clanging of pots and pans.

» READ MORE: The Instacart coronavirus strike is unlike any strike you’ve ever seen

At Monday’s protest, instead of chanting or passing a bullhorn, someone with a powerful sound system blasted Beyoncé’s “Freedom” from car speakers. Then, a couple of activists got on the roof of a car to read a list of demands: for the mayor, judges and governor to take action to reduce the jail, state prison, and immigration detention populations before more people are sickened.

Like all protest actions, this one had its risks. Dozens of drivers received $76 tickets for double parking, according to organizers. A Philadelphia Police Department spokesperson denied that anyone was cited in connection with the demonstration.

Reuben Jones, an organizer with the Philadelphia Community Bail Fund, said he received a citation, but planned to fight it. He thought the show of support was worth the risk, to remind elected officials that the call for action is urgent. “It made a powerful statement. Traffic was locked up, and people were paying attention.”

» READ MORE: SavePhillyEats throws a free financial lifeline to Philadelphia restaurants and bars

Danielle Phillips, a Temple University law student, took a break from what’s become a grueling, 24-hour-a-day slog of schoolwork and parenting, to attend. She piled her two children, Eve, 11, and Owen, 6, into the car for the drive from Narberth — call it home-schooling in civics.

“I tell them this is your duty as a citizen. It’s your duty to care about something," she said. When she saw the line of cars wrapped around City Hall, she said, she was encouraged. “It felt like, here is a large group of people asking for something during a time when it’s pretty inconvenient and even scary to go out.”