Several supporters of the former president have been hospitalized with an unidentified illness following a rally in Tucson, Arizona, last week, raising questions about what might have been present in the environment.

Reports indicate that numerous attendees from the September 12 event have sought medical attention due to symptoms like eye irritation, facial swelling, and itching. The rally, which drew over 2,000 participants in sweltering temperatures exceeding 100 degrees, may have facilitated the spread of some illness among the crowd. Campaign officials are actively trying to trace the outbreak’s origin, while a spokesperson for the Secret Service confirmed that there were no prior threats associated with the event and that nothing unusual occurred that day.

The rally logistics allowed for 48 attendees to be positioned on stage behind former President Donald Trump, split evenly between the left and right sides. Notably, those on the left side reported no symptoms following the event, while several individuals on the right experienced severe eye pain.

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One affected attendee, Mayra Rodriguez a former Planned Parenthood director who has since supported Trump described intense burning in her eyes that made it difficult to see. Fearing she may have been exposed to mace or an aerosol spray, she sought medical attention. Days later, she remained in discomfort, stating, “I can’t see anything. It feels like a white cloud when I try to open my eyes.”

Another attendee labeled her symptoms as “horrible,” while a man from the right side of the stage expressed that his eyes were “red like hell” and he found the experience unbearable. Kathleen Winn, a Trump supporter and former congressional candidate, shared her concern for those affected, hoping the incident wasn’t the result of any malicious intent.

During the rally, Trump reiterated his commitment to eliminating taxes on tips for service workers, a proposal that Vice President Kamala Harris also promoted that evening at a private event nearby. With polling indicating a tight race in Arizona, where Trump and Harris were reported to be tied at 46%, supporters are counting on U.S. Senate candidate Kari Lake to drive turnout among conservative voters in what could be a pivotal election year.