Mia Amalia Cummings, a 29-year-old staff member at All Saints Catholic School, is charged with eight counts of felony lewd acts on a child in connection with the incidents, which involved a 14-year-old boy, said Hayward police Sgt. Ken Forkus.
Court documents show the nearly dozen incidents allegedly took place from December 2011 through this month.
Cummings, who school leaders say has worked as an after-school program assistant at the school since September 2005, was being held on $800,000 bail Monday at Santa Rita Jail in Dublin.
Mike Brown, director of communications with the diocese of Oakland, said Cummings was immediately placed on paid administrative leave following her arrest.
Police said that on Nov. 18 they were notified about potential child sexual abuse taking place at the school at 2280 Second St. after a 14-year-old boy told a school staffer that Cummings had been having inappropriate contact with him.
A subsequent investigation revealed Cummings had allegedly been in a sexual relationship with the victim since he was 12 years old and would communicate with him via cellphone and text messaging.
According to court documents, the student told authorities that he had been molested on 10 occasions dating back to 2011 and that five of the incidents took place in the school kitchen. The other five incidents took place off campus, with one occurring in Cummings' Oakland apartment, the student told investigators. Cummings is not suspected of molesting any other students.
Cummings was arrested without incident on Nov. 26, and prosecutors charged her on Dec. 2 with the eight felony charges.
She is expected to enter a plea on the charges at the Hayward Hall of Justice on Jan. 7.
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