An Immigration and Customs Enforcement official said the agency is aware of his status and plans to take him into custody.
David Manito, 42, was set to be released from jail Friday after the Hennepin County Attorney declined charges.
Manito was released Friday evening, but his immigration status could complicate matters.
Brooklyn Park police learned the man was undocumented while he was initially booked in jail, Deputy Chief Mark Bruley said.
Dixon Police say a student brought a gun to school on Wednesday.
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The Hennepin County attorney's office originally had expected to file charges Friday afternoon, but prosecutors said about 4 p.m. that they want more time to investigate the complex case. "The question is if that student had the mental capacity to willingly consent to the act".
Bruley said an initial sexual encounter occurred before the pair left the restroom.
Brooklyn Park Police Chief Craig Enevoldsen says they believe Manito travels throughout the country.
DHS Administration and Dixon Police began to investigate and realized the student was no longer on campus. The two later returned to the same bathroom to have sex again.
Dixon Police now have School Resource Officers assigned to Dixon High School and Reagan Middle School, and Chief Langloss said in a statement that helped them resolve the potentially risky situation. "He didn't have a visitor's badge, he didn't have any (School District) ID or anything like that, and he said, 'I'm here to see my cousin.' And I'm like, well that's, that's interesting'".