Members of the San Diego Minutemen, many of them given to wearing flag-themed clothing, regularly confront suspected undocumented immigrants like these men at a shopping center in Vista, Calif. Photography by Todd Bigelow

OCEANSIDE, Calif. — For Halloween last year, Jeff Schwilk turned his front yard into "Casa La Migra," a play on the Spanish words for U.S. immigration authorities. To depict the Mexico-California border, he fenced his yard with sheets of corrugated tin, rimmed with coils of black cord representing barbed wire. Border-hopping scarecrows straddled the fence.

Members of the San Diego Minutemen, the nativist extremist group Schwilk founded in 2005, showed up in mock Border Patrol uniforms to greet trick-or-treaters. Over a megaphone dubbed the "Alien-ator," they shouted, "Alto, la migra, la migra," a demand to "halt" that was heard all over the neighborhood. Painted on the tin fence were "ACLU Sucks" and "Enrique is Gay" — a jab, no doubt, at Enrique Morones, director of the pro-immigrant humanitarian organization, Border Angels.

"We discovered there is nothing scarier to an illegal alien (and their little anchor baby goblins) than a mock border fence scene," Schwilk crowed in a later E-mail. "Most people (Americans) thought our theme was hilarious."

Halloween or not, the San Diego Minutemen take year-round pleasure in scaring immigrants. On Saturday mornings, when they travel to the sleepy suburban gas stations where immigrant day laborers go to find work, they create scenes that would play well in a show called "Nativists Gone Wild." They call immigrants "wetbacks" and "Julios." They pull out Mace and threaten passing motorists who disagree with them. Calling those who hire day laborers "slavemasters," they've been known to slap flashing amber police lights on their SUVs and chase the would-be employers down. When they're not busy physically intimidating migrants, they take to the airwaves and the Internet to accuse them, without a shred of evidence, of running child prostitution rings and practicing "voodoo Santeria rituals."

Jeff Schwilk

The group, in short, does not merely target immigration policies it doesn't agree with; it harasses and vilifies individual men and women.

But it's not only immigrants that the San Diego Minutemen (SDMM) have trouble with. Late this winter, police began scrutinizing members and supporters of SDMM for possible involvement in a cruel attack on what little property is owned by the residents of a local migrant camp. Another Minuteman was recently charged in connection with an assault on a group of immigrants and falsifying a police report.

The SDMM also has been rejected by the very groups it borrowed its name from — the Minuteman Project and the Minuteman Civil Defense Corps (MCDC) — because even for these hard-line groups, the SDMM is a bit much. "[T]hey don't abide by our rules, our SOP [standard operating procedure], and would not be considered Minutemen," said Carl Braun, MCDC's California leader.

The group isn't much better off internally. Earlier this year, two SDMM principals who had been romantically involved filed dueling legal actions and traded invective and even, one says, physical blows. Two of its top spokesmen have quit, one of them writing in a subsequent newspaper column that Schwilk "has the ability to schmooze people who, by nature, are peaceful to become angry and vindictive and to commit acts they normally would not even consider."

The San Diego area is no stranger to immigrant-bashing or even more extreme forms of nativism — John Metzger, the son of the White Aryan Resistance leader who lives nearby, still regularly calls in to local radio shows to remind listeners of his father's participation in a 1979 "Klan Border Patrol." But that Klan effort, and most of the nativist attacks of the past, pale in comparison with the SDMM.

"I've been up and down the state," says Claudia Smith, a long-time pro-immigrant activist with the California Rural Legal Assistance Foundation. "There's a rawness to the anti-immigration feeling here. You can almost taste it."

But on this day, the circus of the San Diego Minutemen and a sideshow of pro-immigrant observers already have arrived. The handheld cameras favored by both camps are rolling and the epithets stand ready.

A small black pickup arrives. The driver signals and two Latino immigrants quickly climb into his cab. But the truck can't get out of the lot before one of the Minutemen thrusts his upper body into a window.

"This is not a legal hiring center. Do what's right for your country," the Minuteman admonishes the driver, handing him a list of licensed day labor sites and a flier entitled "Stopping SPP," a reference to a supposed secret government plan to destroy U.S. sovereignty by merging the country into an European Union-style federation with Canada and Mexico.

At another day labor site that day, a Minuteman is yelling at immigrants. "Hey, putas," the man shouts, calling them whores, before he remembers that Spanish has gendered word endings and starts calling the men "putos" instead. The word translates best into the English-language epithet, "faggot." A motorist who's stopped by the Arco station to top off his tank leans out his window to tell off SDMM leader Schwilk. "Hey, Billy boy," he begins.

Furious, Schwilk demands that the man get out of his car. Then the SDMM boss pulls out a can of Mace. "Bring it on, bitch," Schwilk says. "Bring it on." The man drives off instead.

There doesn't seem to be much holding an angry Jeff Schwilk back these days. On another day at the Bonsall day labor site, the SDMM founder was videotaped angrily slapping a magnetized flashing amber light on the roof of his mini-SUV. With the light whirling, he roared away, chasing someone who had just hired a day laborer out of the lot and down the road. A half-hour would elapse before Schwilk returned to the filling station.