The Trump administration is suing the city of Chicago, Cook County and the state of Illinois over sanctuary laws that prohibit local law enforcement from aiding U.S. Immigration and Customs Enforcement in arresting undocumented immigrants.

Why it matters: The lawsuit puts legal pressure on Illinois and other immigration-friendly states as President Trump works to fulfill his campaign promises for mass deportations.

Zoom in: The Justice Department suit claims that local laws impede the federal government from enforcing federal immigration law.

• The complaint says the local laws are "designed to and in fact interfere with and discriminate against the Federal Government's enforcement of federal immigration law in violation of the Supremacy Clause of the United States Constitution."

Context: Chicago's sanctuary city ordinance dates back to 1985.

Zoom out: The lawsuit comes as Trump has ramped up illegal immigration enforcement in Chicago and other major cities since taking office just over two weeks ago.

• Newly sworn-in Attorney General Pam Bondi announced Wednesday that the Department of Justice will withhold federal grants to the Chicago Police Department because of the city's ordinance.
• The DOJ has also threatened to prosecute local officials like Mayor Brandon Johnson and Illinois Gov. JB Pritzker over immigration policies.

What they're saying: "Unlike Donald Trump, Illinois follows the law," a spokesperson for Pritzker said in a statement. "Illinois will defend our laws that prioritize police resources for fighting crime while enabling state law enforcement to assist with arresting violent criminals. We look forward to seeing them in court."

• Pritzker has previously said he welcomes the removal of violent criminals who are undocumented, but stopped short of advocating to change the state law.
• Johnson has not commented on the lawsuit but addressed the challenges to Chicago's law at a Tuesday press conference.
• "I don't believe this is just simply about sanctuary cities; this is really about our democracy," he said. "There are two positions — do you support the constitutional rights for equal protection under the law or do you not?"

What's next: Johnson accepted an invitation to testify before the U.S. House Oversight Committee on March 5 about the city's sanctuary city policies.

False rumors and panic have hit cities coast to coast after federal authorities began a nationwide immigration crackdown, prompting advocates and community leaders to warn people to seek reliable sources of information and keep calm.

Why it matters: Misinformation can ripple through already tense communities, leading to people staying home from work and school.

State of play: Within a couple days of the Trump administration announcing it would allow Immigration and Customs Enforcement officers to conduct enforcement in schools, a false report that ICE offers had showed up to a Chicago elementary school was shared in news reports and even by the governor.

• A similar rumor spread in Philadelphia, prompting the School District of Philadelphia, home to over 198,000 students, to release a statement denying that ICE had been in schools.
• In San Francisco, a middle schooler's claim she'd encountered an ICE agent on a city bus set off panic among parents and others in the city, per a report in the San Francisco Standard.

In immigrant communities in Colorado, online posts warning of raids spread quickly before local police stepped in, saying they were not aware of any action.

• And in Boston on Tuesday, leaders of the Boston Children's Hospital reassured the public that ICE had not raided the facility after several popular social media accounts reposted a false rumor.

What they're saying: "Misinformation is really dangerous because it creates panic and it creates chaos in any community, and immigrant communities are no different," says Conchita Cruz, co-executive director of the Asylum Seeker Advocacy Project (ASAP).

• "I think that part of what is so difficult about this moment for so many immigrants around the United States is that a lot of the executive orders, a lot of the policy changes that are being announced are really not clear."

Between the lines: Top Trump administration officials have made contradictory statements about whether ICE raids would target people with criminal records, or anyone in the country illegally.

• Immigration officials have also not offered specifics as to the circumstances under which they would attempt to arrest someone at a school, for example.
• Whether by design or not, that ambiguity is feeding into the climate of fear and confusion.

The U.S Secret Service says it was their agents, not Immigration and Customs Enforcement agents that showed up at a Chicago Public School (CPS) on the city's South Side Friday.

Why it matters: These were the first reports of agents turning up at a school after the Trump administration announced this week that it would change immigration enforcement policies to allow arrests at schools, churches and hospitals.

• Due to a misunderstanding CPS officials had initially reported denying entry to ICE agents Friday morning.
• The Secret Service agents were "investigating a threat made against a government official we protect," USSS spokesperson Anthony Guglielmi said in a statement.
• He said the agents "identified themselves to the school principal and provided business cards " but "we do not investigate nor enforce immigration laws."

The big picture: Trump's policy change has some parents of undocumented children reconsidering whether to send them to school, AP reports.

• The school, Hamline Elementary, is in a predominantly Mexican-American neighborhood.
• Like many school districts, CPS does not ask students for their immigration status and does not coordinate with immigration enforcement agencies.

How it happened: CPS officials explained late Friday that the confusion stemmed from the agents' presentation of identification from the Department of Homeland Security, which oversees both ICE and the Secret Service. 

• "While this was a misunderstanding in terms of the specific branch of DHS, the school's response demonstrates that our system, in partnership with community organizations, is prepared and ready to keep our students and staff safe," a CPS spokesperson said.

Editor's note: This story has been updated with the latest.

Immigrants and advocacy groups nationwide are scrambling to prepare for the waves of raids President Trump has promised under his plan to deport millions of people unauthorized to stay in the U.S.

Why it matters: Confusion and persistent rumors about how the raids will be carried out — and what will happen to those detained by immigration agents — are leading some anxious immigrants to refuse to go to work or send their children to schools, the groups say.

• Trump's executive orders that began laying the groundwork for his mass deportations reversed several longstanding policies. Immigration officials now can raid churches, schools and hospitals to arrest undocumented immigrants.

State of play: Lawrence Benito, executive director of the Illinois Coalition for Immigrant and Refugee Rights, said his group received 400 calls to its hot line on Monday alone, compared to 800 calls in January before Trump's inauguration.

• The New Mexico-based immigrant rights advocacy group Somos Un Pueblo Unido said it's launching a "Know Your Rights" campaign around the state to help immigrants.
• Other groups are handing out cards to immigrants that advise them to not allow federal agents into their homes without a warrant. Some groups are preparing an army of lawyers to jump into immigration cases.

The intrigue: Denver's public schools are among several districts bracing for possible immigration raids on students. They've directed principals to lock down campuses if federal immigration agents come knocking.

• Some Chicago restaurants are keeping I-9 documents and other worker verification paperwork ready in case of visits by U.S. Immigration and Customs Enforcement (ICE) agents, Eater reports.
• Chicago's police department said in a statement it "will not assist or intervene in civil immigration enforcement," but "as always, we will continue to enforce the law if a crime occurs."
• Police in several other cities are following similar policies.

Trump officials have designated Chicago and other Democrat-run cities as targets of the deportation plan.

• "Unfortunately, part of the goal of this administration is to try to use fear tactics [so] that people go into hiding and maybe people would be deterred and actually leave the country," Greg Chen of the American Immigration Lawyers Association told reporters Tuesday.

Zoom in: Trump advisers initially indicated that ICE would first focus on noncitizens convicted of crimes.

• But the overall plan to crack down on illegal immigration remains unclear — and scattered reports of ICE agents raiding big-city restaurants have many immigrant communities, and business owners, on edge.

Between the lines: Trump has said he favors using the military to help round up immigrants — a move that civil liberties advocates warn would be unlawful.

• The advocates have begun a series of lawsuits fighting Trump's plans, specifically against his order to end birthright citizenship.
• Officials in 22 states have gone to court to challenge Trump's push to end birthright citizenship — a right guaranteed by the 14th Amendment to the U.S. Constitution. An estimated 300,000 babies are born to undocumented parents in the U.S. each year.

Legal specialists say Trump's executive orders on immigration suggest that the president's team is better prepared for challenges to its crackdown on immigration than Trump's first administration was.

• They say several of the orders are written in a way that could insulate the administration from certain legal tactics challenging Trump's plans.
• Some orders, for example, call for a study of an issue and reports to be completed before new actions are taken. The slower approach could build a stronger legal basis for future court decisions.
• "What we're seeing with a second Trump administration is already a recognition of some of the experience of the first Trump administration," Doris Meissner of the Migration Policy Institute told reporters.
• "You can see just by the number of actions that have been prepared and signed within 24 hours how much work and effort behind the scenes has been placed on these executive orders."

The other side: Harrison Fields, White House principal deputy press secretary, tells Axios that those trying to keep undocumented immigrants in the U.S. are swimming "against the tide."

• "Radical leftists can ... reject the overwhelming will of the people, or they can get on board and work with President Trump to advance his wildly popular agenda," Fields said.
• "These lawsuits are nothing more than an extension of the left's resistance — and the Trump administration is ready to face them in court."