The Chicago Police Department says it is investigating an unspecified number of officers for misconduct following allegations they engaged in improper sexual relations with newly arrived migrants.
"These allegations are under investigation with CPD's Bureau of Internal Affairs and the Civilian Office of Police Accountability," a statement from the agency said.
It is unclear how many officers are involved or whether any disciplinary action has been taken.
The allegations were first reported in the Chicago Sun-Times.
Hundreds of migrants have been staying in city buildings over the past several months since being bussed to Chicago after crossing the Mexican border in Texas. The buildings include Chicago police stations where migrants have spent weeks living on the floors while a long-term solution is worked out.
At one point, more than 70 migrant families were sleeping at the city's 12th District police station.
In a statement to CNN, Chicago Mayor Brandon Johnson's office said it was aware of the investigation.
"The City takes these allegations, as well as the care and well-being of all residents and new arrivals, very seriously. We are monitoring the situation closely, but cannot comment further as this is the subject of an ongoing investigation by the Bureau of Internal Affairs and the Civilian Office of Police Accountability," according to the statement.
The Civilian Office of Police Accountability, a police oversight agency, released a statement to CNN that included in part: "Yesterday, the Civilian Office of Police Accountability (COPA) learned of a sexual misconduct allegation involving members of the Chicago Police Department (CPD) assigned to the 10th District and a migrant temporarily housed at the police station."
"While COPA investigators are currently determining whether the facts and details of this allegation are substantiated, we want to assure the public that all allegations of this nature are of the highest priority and COPA will move swiftly to address any misconduct by those involved," said COPA First Deputy Chief Administrator Ephraim Eaddy.
The city has struggled for almost a year to find a more permanent solution for the influx of migrants still arriving from the southern US border. The migrants have traveled thousands of miles from countries throughout Central and South America and from Mexico.
Attempts by the city to place the migrants in community colleges and high schools have been met with fierce resistance from residents at community meetings in those neighborhoods. Johnson's predecessor, Lori Lightfoot, also struggled with finding housing solutions for the migrants when hundreds were bussed to the city from Texas.
Before leaving office in May, Lightfoot issued an emergency declaration after a surge of new migrant arrivals in the city, in what her office called a "national humanitarian crisis."
"We should all understand that the crisis will likely deepen before we see it get better, so as we move forward, the City of Chicago will have to bring additional locations online to prepare for the arrival of more individuals and families and to relieve Chicago Police Department districts," Lightfoot said in a statement.