LA VERNE ( — A 21-year-old teacher’s aide has been arrested on suspicion of having sex with a teenager, authorities said Thursday.

Anthony Michael Valdez of Ontario was a volunteer aide at Ramona Middle School in La Verne.

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He is accused of having a sexual relationship with a girl when she was 13 and Valdez was 20.

Valdez was booked on suspicion of lewd acts with a child under 14 years old and is being held on $100,000 bail.

“The investigation is ongoing as it is unknown at this time if there are any additional victims,” detective Laura Toscano said.

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Officials told CBS2’s Tom Wait the sexual relationship went on for about a year.

They told him the encounters did not take place on the school campus but throughout the area.

La Verne police Capt. Nick Paz says rumors of the relationship spread through the campus and ultimately tipped off a teacher, who told a school police officer.

Paz  said the officer questioned the teen and  she confirmed that there was a sexual relationship.

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Anyone with information regarding this case as well as any additional victims should contact Toscano at (909) 596-1913