Teacher charged with sexual assault on student, 9

TRENTON, N.J. (WTXF) - A Trenton school teacher is under arrest for allegedly sexually assaulting a 9-year-old student.

Robert Ciaccia, 45, taught fourth grade at Franklin Elementary School.

Trenton police and the Mercer County Prosecutor's Special Victims Unit started investigating in May whether he touched the female student's buttocks on two different occasions, and Ciaccia was arrested on Friday.

Ciaccia is charged with two counts of sexual assault and one count of endangering the welfare of a child.

UPDATE: Sex assault charges against NJ teacher dismissed