CHICAGO () As Chicago braces for what is expected to be a large-scale federal immigration enforcement-focused operation that could last six weeks, a suburban Immigration and Customs Enforcement processing center is already seeing activity.

Protests on Friday began at the ICE processing center in west suburban Broadview, where the mayor had warned residents earlier this week that the facility would serve as the main processing hub for the looming multi-agency operation, expected to involve up to 300 ICE and Customs and Border Protection officers in Chicago.

Protesters blocked the entry to the processing center and sat in the street, forcing ICE vans to turn away. Broadview police officers attempted to get protesters to move from blocking the entrance, but were unsuccessful, forcing the detention vehicles to change course.

Early Friday morning, cameras captured detainees at the center being loaded into vans while handcuffed and driven off. Protesters told that detainees are typically transported between 7-9 a.m., but said that the schedule was likely changed due to the anticipation of demonstrators coming to the facility in opposition to ICE activity.

Also on Friday, Chicago’s FBI field office announced that a suburban Chicago man had been arrested by task force officers after officials alleged that the man made death threats against federal law enforcement officers. In a statement, FBI officials said that the agency has “zero tolerance” for anyone who compromises the safety of federal officers.

While the federal officers will be based at Naval Base Great Lakes near the Illinois-Wisconsin border, the ICE processing center is expected to see a daily stream of activity seven days a week for the next 45 days, Broadview Mayor and Village President Katrina Thompson wrote to residents this week.

 Thompson, who did not respond to an interview request from on Friday, wrote to residents that village officials are expecting protests like the one on Friday to continue throughout the operation. She compared the planned demonstrations to those that took place in Los Angeles over the summer, when property damage and assaults on federal immigration enforcement officers took place.

What is known about the Broadview ICE processing center

The center, unlike ICE’s detention centers around the country, is only to process undocumented immigrants who are taken into custody by federal officers.

Once there, the center is specified to hold detainees for no more than 12 hours before they are transferred to a formal detention facility.

Immigration advocates said the facility which is the site of frequent protests has no beds, no showers and no cafeteria. The complaints led four Democratic members of Illinois’ congressional delegation to attempt an unscheduled visit to the site in June.

Earlier this year, a Chicago Tribune investigation found that those held in ICE custody were often kept at the Broadview facility for days rather than hours. The report, citing data shared by the Deportation Data Project, showed that the average detainee was kept at the facility for 2-3 days as opposed to the average of five hours they had been previously.

Emails sent by to ICE and to Sam Olsen, the Chicago ICE director, seeking comment on how the detention center would be used during the upcoming operation, were not immediately returned.

During a news conference Friday at the suburban Naval base, U.S. Sens. Tammy Duckworth and Dick Durbin, both Democrats, said that Department of Homeland Security officials refused to meet with lawmakers do discuss the operation.

“This is not the action of somebody that is proud of what they’re doing,” Duckworth said. “And this is not the action of somebody that is doing something legal.”

House Speaker Mike Johnson, R-La., visited the ICE field office earlier this year before $45 billion in federal dollars added detention centers from President Donald Trump’s mega spending bill was approved by Congress. Johnson told reporters after the visit that like many ICE facilities, the Broadview processing center was in need of upgrades.

“This facility was last updated in 2008, so this is long overdue,” Johnson said. “The technology has changed and a lot of the facility requirements are not being met because they don’t have the funding for it.”

Earlier this week, the doors and windows of the local ICE processing center were boarded up in anticipation of the ramped-up activity. No timeline has been given for when ICE and other federal immigration enforcement agencies will begin the operation, but Illinois Gov. JB Pritzker believes that White House Chief of Staff Stephen Miller planned it around Mexican Independence Day celebrations, which begin on Saturday.

In Broadview, officials say they will be ready to push back against ICE activities, which lawmakers on Friday characterized as political theater and an attempt to intimidate those communities that may be targeted by federal agencies.

“We will defend the constitutionally protected right to peaceful protest and will accept no interference with that right,” Broadview Village administrator LeTisa Jones told the Associated Press. “Simultaneously, we will reject any illegal behavior that puts Broadview police officers’ safety or the safety of local businesses and residents at risk.”