LOS ANGELES (CNS) - City and county officials throughout Los Angeles are planning to join a proposed class-action lawsuit filed by the American Civil Liberties Union against the federal government on behalf of people who allege they were unlawfully stopped or detained by federal agents.

The lawsuit alleges that federal agencies, including U.S. Immigration and Customs Enforcement and U.S. Customs and Border Protection, have engaged in unconstitutional and unlawful immigration enforcement raids by targeting Angelenos based on their perceived race and ethnicity and also denying detainees constitutionally mandated due process.

During a Tuesday news conference in downtown Los Angeles, City Attorney Hydee Feldstein Soto, Mayor Karen Bass and other regional mayors said they plan to assert their rights under the 10th Amendment of the U.S. Constitution, which enshrines the principle of federalism, where the federal government and individuals states share power, by mutual agreement.

"The federal government has concentrated thousands of armed immigration agents, many of whom lack visible identification, and military troops in our communities, conducting unconstitutional raids, roundups and anonymous detentions, sowing fear and chaos among our residents," Feldstein Soto said. "Today's motion to intervene shows we will not stand by and allow these raids to continue or to become the standard operating procedure in our communities."

Bass reiterated her contention that the Trump administration is treating Los Angeles as a test case.

"The city of Los Angeles, along with the county, cities, organizations and Angelenos across L.A., is taking the administration to court to stop its clear violation of the United States Constitution and federal law," Bass said. "We will not be intimidated -- we are making Los Angeles the example of how people who believe in American values will stand together and stand united."

The announcement came one day after local Democrats condemned federal immigration activity at MacArthur Park, where more than 100 agents amassed before leaving without making any arrests.

Speaking Tuesday on Fox News, U.S. Border czar Tom Homan said federal agents targeted the park because it is a hotbed of human-trafficking activity, and a place people go if they're looking to obtain fake Green Cards or Social Security numbers. Homan said no arrests resulted from the operation, because plans of the raid were "leaked" in advance.

Meanwhile, the White House issued a statement Tuesday morning defending federal immigration activity.

"The brave men and women of ICE are under siege by deranged Democrats -- but undeterred in their mission," the White House said in a statement. "Every day, these heroes put their own lives on the line to get the worst of the worst -- criminal illegal immigrant killers, rapists, gangbangers, and other violent criminals -- off our streets and out of our neighborhoods."

L.A. County Supervisor Hilda Solis announced Tuesday afternoon that the county also joined the city's efforts to address allegedly warrantless arrests and seizures caused by ICE raids, authorized by the Department of Homeland Security.

"Today, as a result of that motion, the County of Los Angeles is joining the city of Los Angeles to intervene in a federal class action lawsuit against the Trump administration," Solis said in a statement. "For the past month, we've seen individuals picked up at car washes and Home Depot parking lots, then simply disappear without warrants, probable cause, or due process."

DHS on social media has denied these allegations.

"Claims that individuals have been `targeted' by law enforcement because of their skin color are disgusting and categorically FALSE. DHS enforcement operations are highly targeted, and officers do their due diligence," according to DHS.

"ICE detention facilities have higher standards than most U.S. prisons that hold actual U.S. citizens," DHS previously stated. "These types of smears are designed to demonize and villainize our brave ICE law enforcement. This garbage has directly led to a nearly 700 percent increase in the assaults on ICE law enforcement officers."

Montebello Mayor Salvador Melendez, Monterey Park Mayor Vinh Ngo, Pasadena Mayor Victor Gordo, West Hollywood Mayor Chelsea Byers and Culver City Vice Mayor Freddy Puza attended Tuesday's news conference announcing the legal action. Each mayor showed their support for the city and county's legal actions, and also criticized the Trump Administration's immigration tactics.

In an interview with City News Service, Bass said the federal immigration activity is creating a sense of "fear and terror," and accused U.S. immigration officials of going after those with legal status.

"The Trump administration does have problems with people here with legal status. Otherwise they wouldn't be detaining people when they show up for their annual immigration appointment," Bass told CNS. "They are here legally now. They're talking about canceling temporary status for people=who are from countries that are in conflict."

The latest federal raids took place in Van Nuys on Tuesday, where armed agents reportedly made an unspecified number of arrests in front of a Home Depot, and four people were arrested for allegedly using homemade spike- strips in an effort to disable vehicles involved in the enforcement action.

Tim Conway Jr