A sheriff’s deputy in Colorado briefly pulled over Caroline Dias Goncalves before immigration agents detained her. Now county officials are conducting a review.

Questions are surfacing about the immigration detention of a 19-year-old college student from Utah after a traffic stop in Colorado this month.

Caroline Dias Goncalves, a student at the University of Utah, was driving on Interstate 70 outside Loma on June 5 when a Mesa County sheriff’s deputy pulled her over. The stop lasted less than 20 minutes, and “Dias Goncalves was released from the traffic stop with a warning,” the sheriff’s office said in a news release Monday.

Then, shortly after she exited the highway, Immigration and Customs Enforcement agents stopped her, arrested her and took her to an immigration detention center.

Dias Goncalves is one of nearly 2.5 million Dreamers living in the United States. The word “Dreamer” refers to undocumented young immigrants brought to the United States as children.