From the AP:

The suspected shooter told Sacramento County Sheriff’s investigators that he was 34-year-old Marcelo Marquez of Salt Lake City. However, his fingerprints match the biometric records of a Luis Enrique Monroy-Bracamonte in a federal database, U.S. Immigration and Customs Enforcement spokeswoman Virginia Kice said.

Monroy-Bracamonte was first removed from the country in 1997 after being convicted in Arizona for possession of narcotics for sale. Monroy-Bracamonte was arrested and repatriated to Mexico a second time in 2001, Kice said.