LOS ANGELES (CBS) —  A Los Angeles high school teacher’s aide was sentenced Thursday to 18 years in state prison for sexually abusing two special education students, including one in a wheelchair.

Los Angeles Superior Court Judge Sam Ohta imposed the maximum term on Oscar Enrique Santos of La Puente, who formerly was a teacher’s aide at Garfield High School.

Santos, 45, was convicted of 21 felony charges, including oral copulation of an incompetent person, oral copulation of a person under 18 and sexual battery by restraint.

The charges involved two developmentally disabled girls — ages 16 and 17 at the time — who were sexually abused between 2005 and 2007, according to the District Attorney’s Office.

Santos — who was responsible for assisting a gravely disabled male student — attacked the two girls between classes in an on-campus elevator, said Deputy District Attorney Rachel Moser Greene.

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