Many questions remain about what happened at Hamline Elementary when Chicago Public Schools mistook Secret Service agents for immigration enforcement.

U.S. Immigration and Customs Enforcement agents attempted entry into a Chicago elementary school Friday morning, but were not allowed inside or permitted to speak to anyone inside, Chicago Public Schools officials said.

The U.S. Secret Service says their agents came to the school to investigate a threat, not to enforce immigration laws. Their arrival spread fear in a community on high alert.