Ahead of a federal hearing over Harvard University's ability to enroll international students, the acting director of the U.S. Immigration and Customs Enforcement issued a letter Thursday giving the school 30 days to challenge the administration's revocation of that certification.

San Diego County is included on the list, as well as the cities of San Diego, Vista, Chula Vista and Santee. “These sanctuary city politicians are endangering Americans and our law enforcement in order to protect violent criminal illegal aliens,” DHS Secretary Kristi Noem said in a news release.