After allegedly slamming into a school bus full of 28 elementary-school children and driving away, Jonathan Carillo-Rubio tried to tell the cops he was just a scared kid -- until they found out he wasn't a kid, but a well-known human smuggler.

The Arizona Department of Public Safety says Carillo-Rubio, 20, was driving on Interstate 10 in a stolen truck around 3 p.m. Thursday when he nailed a school bus with 28 young kids inside, sending two to the hospital.

Carillo-Rubio drove away from the scene, but the truck broke down on an off-ramp at 35th Avenue.

A DPS patrolman pulled up to the truck when Carillo-Rubio then tried to run away on foot -- before being caught a short time later by Phoenix police officers.

Carillo-Rubio told police he was a juvenile and gave them a fake date of birth, that is, until detectives from IIMPACT (Illegal Immigration Prevention & Apprehension Co-op Team) identified him as a 20-year-old human smuggler that wanted by Border Patrol officials.

Police say Carillo-Rubio was in the country illegally, and had entered the country illegally on numerous occasions, working as a human smuggler or foot guide to get other illegal immigrants into the U.S.

Now police say Carillo-Rubio faces charges of hit and run, three counts of aggravated assault, and 27 counts of endangerment.

The two kids hospitalized from the crash were treated for minor injuries.