MINNEAPOLIS (AP) - Immigration officials say they've identified the driver of a van that hit a school bus in a crash that killed four children in southwestern Minnesota.

Authorities say it was 24-yearold Olga Marina Franco, who they say is from Guatemala. The woman first gave investigators the name Alianiss Nunez Morales and told them she was from Mexico.

Immigration officials have filed paperwork to keep Franco in custody. Authorities in Lyon County have charged her with four counts of criminal vehicular homicide. She's also charged with running a stop sign and driving without a license.