Michael Guidotti will have his driver’s license on him when he runs the Chicago Marathon, just as he did during every training run since summer.

After the Trump administration escalated its immigration crackdown in the city, runners like Guidotti, 31, are worried they could become a target during Sunday’s race.

“Just knowing that I do come from a Hispanic background and also that I am somewhat darker, and that these individuals do seem to be targeting people of that demographic as well,” Guidotti said. “So it’s just an extra precaution that I’m taking that I have my driver’s license with me at all times.”

Questions have been swirling for weeks over whether Immigration and Customs Enforcement agents might target the marathon, which draws thousands of runners from around the world each year. Reflecting the unease, event organizers sent an email to participants Wednesday that referred to an immigration “Know Your Rights” page on the city’s website.

An ICE spokeswoman, Tanya Roman, said rumors that agents will be at the race are false.

“It’s absolutely ridiculous to ascertain that ICE would conduct immigration enforcement to intentionally disrupt the Chicago marathon,” she said in a statement. “These are the kind of rumors that fan the flames of dissent and result in unwarranted and dangerous riots like those in Portland, Chicago and Los Angeles.”

Such assurances might not calm the fears of some participants, though.

Chicago has become a top target of the Trump administration, which has escalated immigration enforcement in the city through aggressive raids and tactics. The Chicago Marathon is one of the biggest in the U.S. each year and is a major tourism draw for the city. There were 52,150 finishers last year, of which 15,000 were international participants, according to race organizers, who didn’t respond to requests for comment. Among foreign countries, Mexico was best represented, with 3,790 participants.

Enrique Rivera, who leads Pilsen's Venados Running Club, isn't expecting a lively atmosphere from onlookers this year.

“I’m absolutely sure that people are going to stay home,” he noted. “There’s street vendors that aren’t out on the street doing their sales that impact their life. I’m sure they’re also going to be able to cut off recreational activities like cheering on runners.”

Community leaders like Michael Rodriguez, an alderman for Chicago's 22nd ward, express concern about the potential economic impact on local businesses due to decreased turnout. The mayor, however, remains optimistic, stating that plans are in place to ensure the marathon proceeds without issue.