Why it matters: The largest number of single-day arrests announced by Immigration and Customs Enforcement since Trump took office last Monday and declared a national emergency on the U.S.-Mexico border is a clear sign that his administration is stepping up efforts crack down on undocumented immigrants.

The Trump administration launched an immigration enforcement blitz in Chicago on Sunday that includes several federal agencies that have been granted additional authorities to arrest undocumented immigrants in the US,

A top Department of Justice official is in Chicago on Sunday to oversee immigration efforts by multiple agencies, according to officials. Acting Deputy Attorney General Emil Bove, appointed by President Trump,

Border czar Tom Homan told NBC News that several people with criminal convictions were apprehended in Chicago.

State and local leaders across the country are bracing for a tidal wave of aggressive immigration policies and possible mass deportations that President Donald Trump has vowed to enact in the hours and days following his inauguration Monday.

With two top Trump administration officials in Chicago, federal law enforcement began a “targeted” immigration blitz Sunday, according to a spokesman for U.S. Immigration and Customs Enforcement. The agency did not say how many arrests have taken place so far.