On Tuesday, June 17th, Nancy Urizar was at her job working in the fund-raising department of a Jesuit boys’ high school in the Los Angeles neighborhood of Watts when her phone rang. “It was just a normal day for me,” she said. “It was twelve, and I had just come back from lunch.” On the other end of the line was her father’s landlord. Some friends of her dad’s had come over, the landlord told her, and they were asking for her phone number. Since June 6th, when two significant raids on undocumented immigrants in Los Angeles marked the beginning of an escalation of operations by Immigrations and Customs Enforcement, it has been a time of fear and anxiety. “She didn’t want to open the door because she was scared,” Urizar told me. But the friends turned out to be colleagues of her father, Francisco Urizar, who worked delivering Mission-brand products, including tortillas, to local grocery stores. “She was, like, I have your dad’s friends and they’re saying that they saw—I think, on the news or on social media—that there was a video, and it was my dad that got taken,” Urizar said. “I’m, like, in shock. I’m, like, stop playing this joke on me. It’s not funny.”

The video was recorded by a bystander at a Food 4 Less grocery store in the city of Pico Rivera in eastern L.A. County at nine-thirty that morning. It shows a parked yellow box truck with a homemade-looking paint job, next to which stands a group of immigration agents dressed in camouflage, helmets, and flack jackets, and holding what appear to be rifles. They wear neck buffs pulled up to hide their faces, sunglasses, and gloves, and are laden with tactical gear, as if in a combat zone and not a suburban parking lot. Francisco Urizar has been interrupted mid-delivery and, flanked by two of the agents, waits next to a dolly stacked with boxes of food. As the person recording comes closer to the scene, some bystanders shout out advice: “¡No diga nada!” (“Don’t say anything!”); “¡Hasta que tiene un lawyer presente no diga nada!” (“Until you have a lawyer present don’t say anything!”) Francisco wears a blue baseball cap and has a mustache. As the agents lead him to the back seat of a white Customs and Border Protection S.U.V., he glances back anxiously at his truck and the tortillas. “Fucked up, man, la migra,” the person recording says, as he walks closer and zooms in. Other bystanders have harsher words for the agents. “I hope you guys are fucking happy! Go home, fuck your wives,” a woman yells at them. “And you, too, fucking Captain Underpants. You think you’re fucking happy about the little uniform you got going on?” Then the video ends.

I had first seen an Instagram post about Francisco Urizar’s detention on the account of an immigrant-advocacy group called Siempre Unidos L.A., less than two hours after it was reported to have happened. Since June 6th, videos of masked federal agents detaining immigrants across Los Angeles County have been appearing on social media every day. Under state law, the Los Angeles Police Department and other local law-enforcement agencies are limited from assisting federal immigration enforcement, and many municipal governments, having declared themselves sanctuary cities, claim to be in the dark about the time and location of specific federal immigration actions. (In a response to a request for comment, the Department of Homeland Security said that it had alerted the L.A.P.D. two days before beginning the ICE operation in L.A. However, an L.A.P.D. spokesperson said that the department does not receive advance or real-time information about specific raids.) As such, the videos, often captured by bystanders and then aggregated by activist groups or local-news accounts, have become a primary record of what is going on; the federal government is not offering detailed information about where people are taken. One organization, the Coalition for Humane Immigrant Rights, estimates that between five and six hundred people have been detained in the greater Los Angeles area since June 6th. The estimate is “not scientific,” Jorge-Mario Cabrera, the organization’s communications director, told me, adding, “Our approximation is based on the numbers of folks who get reported by the public, the media, and people who call our hotline.” The ICE agents knock on doors, but they have also been detaining people at L.A. bus stops, gas stations, car washes, food trucks, Walmarts, and Home Depots.

After Urizar told the landlord to share her phone number, her father’s colleagues called her and asked if she had a set of keys to his truck, which was still sitting in the loading zone of the grocery store. She didn’t. Unsure of what to do, she left work and called her younger sister, Francis, as she drove fourteen miles to the Food 4 Less. When Urizar arrived, Francis was already there, crying. Urizar, who is thirty years old, felt a responsibility to keep it together.

Urizar told me this the next morning over a waffle at Pancake Corner, a diner in South Gate, the city in southern L.A. County where she lives. She had been up since five in the morning, she said, and looked fatigued but calm. She told me that she had turned to her Christian faith to sustain her through the crisis. “I’m holding on to God’s word,” she said. “Whatever is God’s will, it’s going to be good, and it’s going to be his will, and that gives me peace, that gives me hope, and, honestly, that’s the thing that’s calming me down.” We waited until a server wearing a uniform poured us coffees, and then Urizar talked about her father.

Francisco Urizar, who is sixty-four years old, came to the United States from Guatemala more than thirty years ago, she told me, fleeing the civil war and looking to earn money to support four children left behind in his native country. After arriving, he met Nancy’s mother, who is from Honduras, and had two more children, Nancy first, and then Francis two years later.

“He had a drinking problem when I was younger,” Urizar said. “So he had a domestic-violence report, and we were separated.” (The case was later dismissed.) Because of her parents’ custody arrangement, from the age of eight until she was eighteen Urizar saw her father only once a week. But after her parents’ marriage ended, she said, he turned his life around. “He just solely focussed on working,” she said. “Working to clean his record, working to sustain his family in Guatemala and to sustain us—he’s just been working all his life. And now he lives by himself, has no wife, has no other kids, and he just has me and my sister here.” She had no idea if her father was targeted because her mother had once sought a restraining order or if he was racially profiled, as some of those stopped by immigration agents in recent days appear to have been. (The Department of Homeland Security told me in a written statement, “DHS enforcement operations are highly targeted, and officers do their due diligence.” It also said, “Any claims that individuals have been ‘targeted’ by law enforcement because of their skin color are disgusting and categorically FALSE.”)

“He made mistakes,” she said, “but they’re old mistakes, like twenty-plus-years-old mistakes.” And while she said that he may not have been a good husband, she considered him a devoted father. “I’ve always loved my dad,” she told me. “He’s, like, a great dad, he’s the best dad, and I’m not just saying that because he’s my dad, but he’s such a good dad. Like, everything I have is because of my dad.”

In Los Angeles in recent weeks, a popular phrase has been revived on protest signs and social-media posts: “Solo el pueblo salva al pueblo,” or, “only the people can save the people.” In L.A., although the city and county law-enforcement agencies are restricted from assisting ICE, they are not working to actively impede the federal agents, either. Local groups and nonprofits have taken on the task of not only documenting the raids but also teaching people how to protect themselves. The most prominent of these is the Community Self-Defense Coalition, a network of more than sixty advocacy groups, including Black Men Build, the Harriet Tubman Center for Social Justice, and the local chapter of Jewish Voice for Peace. It was formed in February, in the early days of the second Trump Administration, after documents leaked to the L.A. Times indicated plans for a “large scale” immigration enforcement action in the city.

At six in the morning last Saturday, Ron Gochez, a teacher at a public high school, got in the front passenger seat of an S.U.V. parked outside a laundromat in Los Angeles’s South Central neighborhood. Gochez is an organizer for Unión del Barrio, a nonpartisan political group that is part of the Community Self-Defense Coalition and advocates for the rights of Mexican Americans and other people of Latin American descent. (The driver, a volunteer in a medical mask, asked not to be identified.) “Welcome to South Central Los Angeles,” Gochez said, as we rolled out of the parking lot, passing a street sign that had been graffitied with the words “Dump Trump.” “That’s how our community feels,” Gochez said. The two were part of the Unión del Barrio community patrol, whose aim is to monitor—and warn the neighborhood about—the presence of federal agents. During the past two weeks, the patrol had been sending cars out every morning.

A few minutes earlier, a dozen volunteers, mostly women, had gathered in a circle in the parking lot; most wore black pants and green hoodies printed with the profile of a Mexica eagle warrior, the Unión del Barrio emblem. The group had distributed walkie-talkies and placed magnets on their cars which bore the Unión insignia and read “PROTECTING COMMUNITIES FROM ICE & POLICE TERROR” in English and Spanish. There were also flyers to inform residents of numbers to call if they saw vehicles characteristic of those traditionally dispatched by ICE: U.S.-made models such as Ford Explorers or Chevy Tahoes with ultra-dark tinted windows, police gates separating the front seats from the back, and, at times, dealership placards or no license plates.